Statistics Questions

5 G Que 4 3 2 1 S G Select an answer Quadrant I Quadrant II Quadrant III Quadrant IV x axis C Quic 5 4 E 30 2 1 1 F 2 3 4 5 For each point on the graph above select the correct location from the drop down list A Select an answer B Select an answer C Select an answer D Select an answer E Select an answer F Select an answer 1000 o forum B B 2 imp to Answer 3 4 5

Give the slope and the y intercept of the line y 62 6 Make sure the y intercept is written as a coordinate This means the y intercept must be in the form 0 b Slope y intercept

B 80 C B 5 4 3 2 1 A C 30 2 1 123 D 30 4 5 1 Identify the points from the graph above and write as ordered pairs REMEMBER Ordered pairs are written with parentheses A 2 3 4 5

About how many alcohol related deaths occurred in 1991 DEATHS Alcohol Related Traffic Deaths thousands 23 22 20 H 19 S 18 17 16 89 90 91 92 93 94 95 Year Despite the efforts by groups such as MADD Mothers Against Drunk Driving the number of alcohol related deaths is rising after many years of decline Choose the number of alcohol related deaths in 1991 15500 17000 20000 O23000

The graph below shows the temperature of a cup of coffee after some number of minutes 50 40 30 20 10 10 mintes 20 Estimate the temperature after 10 minutes

The graph below shows the temperature of a rock after some number of minutes 60 50 40 30 20 degrees 10 minutes 20 What is the temperature after 10 minutes You must be within 4 degrees degrees Answer

The line graph below shows the pieces of candy Sylvia ate each day of last week IU L 8 7 6 S 4 3 2 2 6 7 1 Day of Week How many pieces of candy did Sylvia eat on day 6

1 The line graph below shows the number of times Maria drove her car each day of the week 1J 14 13 12 11 10 9 8 7 6 5 3 2 1 2 3 Question Help Worked 5 6 Day of Week How many times did Maria drive her car on day 4 7 a

Give a 95 confidence interval for 2 given the following information n 45 1 2 94 81 0 7 n 50 T 2 91 82 0 55 Rounded both solutions to 2 decimal places H

1 Consider the following two way frequency table relating couple success to long distance relationships in America If an American couple was chosen at RANDOM calculate the probabilities being asked below Got Married Broke Up Total Same City 12 18 30 Same state but different city 8 22 30 1 a Are the two events being analyzed MUTUALLY EXCLUSIVE Explain P Ended in Marriage Medium Distance P Short Distance Ended in Marriage P Ended in Marriage U Long Distance 1 b Suppose that a couple in America is chosen at random consider the probabilities Different States P Long Distance Did Not End in Marriage S 5 15 20 Total 25 55 80

Put the following critical values in numerical order from largest to smallest a 20 02 b to 02 with 15 degrees of freedom c to 02 with 35 degrees of freedom This is a reading assessment question Be certain of your answer because you only get one attempt on this question Choose the correct answer below O b a c O a c b O c b a O b c a O a b c O c a b

In a survey 1000 adults in a certain country were asked how many hours they worked in the previous week Based or the results a 95 confidence interval for mean number of hours worked was lower bound 37 2 and upper bound 38 9 Which of the following represents a reasonable interpretation of the result For those that are not reasonable explain the flaw Complete parts a through d below a There is a 95 chance the mean number of hours worked by adults in this country in the previous week was between 37 2 hours and 38 9 hours OA Flawed This interpretation makes an implication about individuals rather than the mean OB Flawed This interpretation implies that the population mean varies rather than the interval OC Correct This interpretation is reasonable OD Flawed This interpretation implies that the mean is only for last week

6 A researcher polled a sample of 1092 adults in the year 2010 asking them how many hours per week they spent on the Internet The sample mean was 9 39 with a standard deviation of 13 30 A second sample of 1040 adults was taken in the year 2012 For this sample the mean was 10 55 with a standard deviation of 14 56 Assume these are simple random samples from populations of adults Can you conclude that the mear number of hours per week spent on the Internet increased between 2010 and 2012 Let 1 denote the mean number of hours spent on the Internet in 2010 and 2 denote the mean number of hours spent on the Internet in 2012 Use the a 0 10 level and P value method with TI 84 calculator State the appropriate null and alternate hypotheses b This is a Left tailed Two tailed Right tailed test Circle the correct answer c Compute the P value Round the answer to four decimal places d Decision Determine whether to reject Ho e State your conclusion

In the game of roulette a player can place a 10 bet on the number 32 and have a probability 38 of winning If the metal ball lands on 32 the player gets to keep the 10 paid to play the game and the player is awarded an additional 350 Otherwise the player is awarded nothing and the casino 2023 takes the player s 10 What is the expected value of the game to the player If you played the game 1000 times how much would you expect to lose Note that the expected value is the amount on average one would expect to gain or lose each game The expected value is 0 53 Round to the nearest cent as needed The player would expect to lose about Round to the nearest cent as needed e game c al ball lan 0 Otherw

A strain of bacteria is placed into a petri dish at 30 C and allowed to grow The following data are collected Theory states that the number of bacteria in the petri dish will initially grow according to the law of uninhibited growth The population is measured using an optical device in which the amount of light that passes through the petri dish is measured Complete parts a e Time hours X 0 234 2 5 3 5 4 5 6 Population y 0 27 0 53 0 76 1 03 1 46 a Treating time x as the predictor variable use a graphing utility to fit an exponential fun the data y ab Round to four decimal places as needed

1 38 probability of winning If the metal ball lands on 32 the player gets to keep In the game of roulette a player can place a 10 bet on the number 32 and have a the 10 paid to play the game and the player is awarded an additional 350 Otherwise the player is awarded nothing and the casino takes the player s 10 What is the expected value of the game to the player If you played the game 1000 times how much would you expect to lose Note that the expected value is the amount on average one would expect to gain or lose each game The expected value is Round to the nearest cent as needed The player would expect to lose about Round to the nearest cent as needed

A report set a goal of 0 541 for the proportion of babies still being breastfed one year after birth The organization also used the survey data to estimate the proportion who were still being breastfe one year after birth to be 0 351 for babies born in a particular year Suppose that the survey used a random sample of 1 000 parents and that you want to use the survey data to decide if there is evidence that the goal is not being met Let p denote the population proportion of all babies born in that particular year who were still breastfeeding at 12 months Hint See Example 10 10 USE SALT The shape of the sampling distribution is approximately normal The sampling distribution is centered at 0 541 0 0158 MY NOTES a Describe the shape center and variability of the sampling distribution of p for random samples of size 1 000 if the null hypothesis Ho P 0 541 is true Round your standard deviation to four decimal places PRACTICE ANOTH The standard deviation of the sampling distribution is b Would you be surprised to observe a sample proportion as small as p 0 532 for a sample of size 1 000 if the null hypothesis Ho p 0 541 were true Explain why or why not Round your answer to four decimal places Consider the event surprising if the probability the event occurs when Ho p 0 541 is true is less than 0 05 We would not 0 be surprised to observe a sample proportion of p 0 532 for a sample of size 1 000 if the null hypothesis Ho p 0 541 is true The probability of a sample proportion this small or smaller is 0 2843 which is greater than 0 05 c Would you be surprised to observe a sample proportion as small as p 0 507 for a sample of size 1 000 if the null hypothesis Ho p 0 541 were true Explain why or why not Round your answer to four decimal places Consider the event surprising if the probability the event occurs when Ho p 0 541 is true is less than 0 05 Since the probability of a sample proportion this small or smaller is 0 met We would 0 be surprised to observe a sample proportion of p 0 507 for a sample of size 1 000 if the null hypothesis Ho p 0 541 is true The probability of a sample proportion this small or smaller is 0 006 X which is less than 0 05 d The actual sample proportion observed in the study was p 0 351 Based on this sample proportion is there convincing evidence that the goal is not being met or is the observed sample proportion consistent with what you would expect to see when the null hypothesis is true Round your answer to four decimal places Consider the evidence that the goal is not being met convincing if the probability the event occurs when Ho P 0 541 is true is less than 0 05 which is less than O 0 05 there is convincing evidence that the goal is not being

K A nutritionist wants to determine how much time nationally people spend eating and drinking Suppose for a random sample of 925 people age 15 or older the mean amount of time spent eating or drinking per day is 1 28 hours with a standard deviation of 0 64 hour Complete parts a through d below GEILE a A histogram of time spent eating and drinking each day is skewed right Use this result to explain why a large sample size is needed to construct a confidence interval for the mean time spent eating and drinking each day OA The distribution of the sample mean will never be approximately normal OB The distribution of the sample mean will always be approximately normal OC Since the distribution of time spent eating and drinking each day is normally distributed the sample must be large so that the distribution of the sample mean will be approximately normal OD Since the distribution of time spent eating and drinking each day is not normally distributed skewed right the sample must be large so that the distribution of the sample mean will be approximately normal b There are more than 200 million people nationally age 15 or older Explain why this along with the fact that the data were obtained using a random sample satisfies the requirements for constructing a confidence interval OA The sample size is less than 5 of the population OB The sample size is greater than 5 of the population C The sample size is greater than 10 of the population OD The sample size is less than 10 of the population c Determine and interpret a 90 confidence interval for the mean amount of time Americans age 15 or older spend eating and drinking each day Select the correct choice below and fill in the answer boxes if applicable in your choice Type integers or decimals rounded to three decimal places as needed Use ascending order OA The nutritionist is 90 confident that the amount of time spent eating or drinking per day for any individual is between and hours OB There is a 90 probability that the mean amount of time spent eating or drinking per day is between and hours OC The nutritionist is 90 confident that the mean amount of time spent eating or drinking per day is between and hours OD The requirements for constructing a confidence interval are not satisfied d Could the interval be used to estimate the mean amount of time a 9 year old spends eating and drinking each day Explain OA Yes the interval is about the mean amount of time spent eating or drinking per day for people people age 15 or older and can be used to find the mean amount of time spent eating or drinking per day for 9 year olds OB Yes the interval is about individual time spent eating or drinking per day and can be used to find the mean amount of time a 9 year old spends eating and drinking each day O C No the interval is about individual time spent eating or drinking per day and cannot be used to find the mea time spent eating or drinking per day for specific age O D No the interval is about people age 15 or older The mean amount of time spent eating or drinking per day for 9 year olds may differ

In a survey conducted by a reputable marketing agency 253 of 1000 adults 19 years of age or older confessed to bringing and using their cell phone every trip to the bathroom confessions included texting and answering phone calls Complete parts a through f below Click here to view the standard normal distribution table page 1 Click here to view the standard normal distribution table page 2 a What is the sample in this study What is the population of interest Determine the sample in this study Select the correct choice below and if necessary fill in the answer box within your choice OA The sample is the adults 19 years of age or older Type a whole number OB The sample is all adults with a cell phone OC The sample is all adults OD The sample is all adults 19 years of age or older Determine the population of interest Select the correct choice below and if necessary fill in the answer box within your choice OA The population is the Type a whole number OB The population is all adults OC The population is all adults 19 years of age or older OD The population is all adults with a cell phone b What is the variable of interest in this study Is it qualitative or quantitative The variable of interest is adults 19 years of age or older because c Based on the results of this survey obtain a point estimate for the proportion of adults 19 years of age or older who bring their cell phone every trip to the bathroom p 0 Round to three decimal places as needed This variable is d Explain why the point estimate found in part c is a statistic Explain why it is a random variable What is the source of variability in the random variable Why is the point estimate found in part c a statistic OA It is information obtained from a survey OB It is being used to make inferences OC Its value is based on a sample OD The sample size is large

A publisher reports that 39 of their readers own a laptop A marketing executive wants to test the claim that the percentage is actually more than the reported percentage A random sample of 400 found that 45 of the readers owned a laptop Is there sufficient evidence at the 0 05 level to support the executive s claim Step 2 of 7 Find the value of the test statistic Round your answer to two decimal places

A publisher reports that 39 of their readers own a laptop A marketing executive wants to test the claim that the percentage is actually more than the reported percentage A random sample of 400 found that 45 of the readers owned a laptop Is there sufficient evidence at the 0 05 level to support the executive s claim Step 1 of 7 State the null and alternative hypotheses Answer Ho Keypar Keyboard Shortca Tables

Days before a presidential election a nationwide random sample of registered voters was taken Based on this random sample it was reported that 52 of registered voters plan on voting for Robert Smith with a margin of error of 3 The margin of error was based on a 95 confidence level Fill in the blanks to obtain a correct interpretation of this confidence interval confident that the of registered voters We are Robert Smith is between We are Robert Smith is between confident that the and 0 and of registered voters planning on voting for planning on voting for

Put the following critical values in order from least to greatest to 10 with 7 degrees of freedom to 10 with 19 degrees of freedom 20 10 Choose the correct answer below O A to 10 with 19 degrees of freedom Z0 10 to 10 with 7 degrees of freedom OB to 10 with 7 degrees of freedom Z0 10 to 10 with 19 degrees of freedom OC Zo 10 to 10 with 19 degrees of freedom to 10 with 7 degrees of freedom OD Zo 10 to 10 with 7 degrees of freedom to 10 with 19 degrees of freedom O E to 10 with 7 degrees of freedom to 10 with 19 degrees of freedom Z0 10 OF to 10 with 19 degrees of freedom to 10 with 7 degrees of freedom Z0 10

on the General Social Survey was When you drink how many drinks do you have The survey was administered to a random sample of 243 adult Americans aged 21 or older Use the data to complete parts a through h Click here to view the data for the number of drinks Click here to view the table of critical t values a What type of variable is number of drinks O A A discrete quantitative variable because all the possible values in the data set are countable OB A continuous quantitative variable because all the possible values in the data set are countable OC A qualitative variable because the data values allow for classification based on the number of drinks consumed OD A continuous quantitative variable because there are an infinite number of possible values that are not countable OE A discrete quantitative variable because there are an infinite number of possible values that are not countable b Construct a histogram of the data and comment on the shape of the distribution Choose the correct graph below O A AFrequency 120 O B 120 TILL 0 4 8 12 Number of drinks 0 4 8 12 Number of drinks AFrequency 120 What is the shape of the distribution O C OA The distribution is skewed right OB The distribution is bimodal OC The distribution is skewed left COD The distribution is roughly symmetric 0 Frequency 0 4 8 12 Number of drinks c Determine the mean and standard deviation for number of drinks The mean number of drinks is Type an integer or decimal rounded to two decimal places as needed The standard deviation is Type an integer or decimal rounded to two decimal places as needed d What is the mode number of drinks O D Q AFrequency 120 04 0 4 8 12 Number of drinks Q

point s possible K A nutritionist wants to determine how much time nationally people spend eating and drinking Suppose for a random sample of 925 people age 15 or older the mean amount of time spent eating or drinking per day is 1 28 hours with a standard deviation of 0 64 hour Complete parts a through d below SEOR a A histogram of time spent eating and drinking each day is skewed right Use this result to explain why a large sample size is needed to construct a confidence interval for the mean time spent eating and drinking each day OA The distribution of the sample mean will never be approximately normal OB The distribution of the sample mean will always be approximately normal OC Since the distribution of time spent eating and drinking each day is normally distributed the sample must be large so that the distribution of the sample mean will be approximately normal Submit test O D Since the distribution of time spent eating and drinking each day is not normally distributed skewed right the sample must be large so that the distribution of the sample mean will be approximately normal b There are more than 200 million people nationally age 15 or older Explain why this along with the fact that the data were obtained using a random sample satisfies the requirements for constructing a confidence interval OA The sample size is less than 5 of the population OB The sample size is greater than 5 of the population C The sample size is greater than 10 of the population OD The sample size is less than 10 of the population c Determine and interpret a 90 confidence interval for the mean amount of time Americans age 15 or older spend eating and drinking each day Select the correct choice below and fill in the answer boxes if applicable in your choice Type integers or decimals rounded to three decimal places as needed Use ascending order OA The nutritionist is 90 confident that the amount of time spent eating or drinking per day for any individual is between and hours OB There is a 90 probability that the mean amount of time spent eating or drinking per day is between hours OD The requirements for constructing a confidence interval are not satisfied OC The nutritionist is 90 confident that the mean amount of time spent eating or drinking per day is between and hours and d Could the interval be used to estimate the mean amount of time a 9 year old spends eating and drinking each day Explain OA Yes the interval is about the mean amount of time spent eating or drinking per day for people people age 15 or older and can be used to find the mean amount of time spent eating or drinking per day for 9 year olds OB Yes the interval is about individual time spent eating or drinking per day and can be used to find the mean amount of time a 9 year old spends eating and drinking each day OC No the interval is about individual time spent eating or drinking per day and cannot be used to find the mean time spent eating or drinking per day for specific age OD No the interval is about people age 15 or older The mean amount of time spent eating or drinking per day for 9 year olds may differ

In a survey conducted by a reputable marketing agency 253 of 1000 adults 19 years of age or older confessed to bringing and using their cell phone every trip to the bathroom confessions included texting and answering phone calls Complete parts a through f below Click here to view the standard normal distribution table page 1 Click here to view the standard normal distribution table page 2 UE its value may change depending on the individuals in the survey Why is the point estimate found in part c a random variable A It is being used to make inferences OB Its value is based on a sample OC Its value may change depending on the individuals in the survey O D The sample size is large OE It is information obtained from a survey What is the source of variability in the random variable OA The question asked in the survey OB The individuals selected to be in the study OC The sample size OD Random errors e Construct and interpret a 95 confidence interval for the population proportion of adults 19 years of age or older who bring their cell phone every trip to the bathroom Select the correct choice below and fill in any answer boxes within your choice Type integers or decimals rounded to three decimal places as needed Use ascending order O A We are confident the proportion of adults 19 years of age or older who bring their cell phone every trip to the bathroom is between and OB There is a probability the proportion of adults 19 years of age or older who bring their cell phone every and trip to the bathroom is between f What ensures that the results of this study are representative of all adults 19 years of age or older OA The high confidence level OB Random sampling OC The large sample size OD Sampling from adults 19 years of age or older

Which of the following are properties of the Student s t distribution Select all that apply A The t distribution is centered at B At the sample size n increases the density curve of t gets closer to the standard normal density cur C The t distribution is the same for different degrees of freedom D The area under the t distribution curve is 1 E The area in the tails of the t distribution is slightly greater than the area in the tails of the standard na distribution

should be obtained if she wishes the estimate to be within 0 02 with 90 confidence if adults who have high speed Internet access What size sample a she uses a previous estimate of 0 32 b she does not use any prior estimates Click the icon to view the table of critical values a n b n Round up to the nearest integer Round up to the nearest integer Table of critical values Level of Confidence 1 a 100 90 95 99 Area in Each Tail 0 05 0 025 0 005 a 2 Critical Value z 1645 1 96 2 575 X

Annie is concerned over a report that a woman over age 40 has a better chance of being killed by a terrorist than of getting married A study found that the likelihood of marriage for a never previously wed 40 year old university educated American woman was 3 4 To demonstrate that this percentage is too small Annie uses her resources at the Baltimore Sun to conduct a simple random sample of 457 never previously wed university educated American women who were single at the beginning of their 40s and who are now 45 Of these women 24 report now being married Does this evidence support Annie s claim at the 0 05 level of significance that the chances of getting married for this group is greater than 3 4 Step 3 of 3 Draw a conclusion and interpret the decision Answer Keypad Keyboard Shortcuts Tables We reject the null hypothesis and conclude that there is insufficient evidence at a 0 05 level of significance that the chance of getting married for a never previously wed 40 year old university educated American woman is greater than 3 4 We reject the null hypothesis and conclude that there is sufficient evidence at a 0 05 level of significance that the chance of getting married for a never previously wed 40 year old university educated American woman is greater than 3 4 We fail to reject the null hypothesis and conclude that there is sufficient evidence at a 0 05 level of significance that the chance of getting married for a never previously wed 40 year old university educated American woman is greater than 3 4 We fail to reject the null hypothesis and conclude that there is insufficient evidence at a 0 05 level of significance that the chance of getting married for a never

Consider the relationship between the number of bids an item on eBay received and the item s selling price The following is a sample of 5 items sold through an auction Price in Dollars 20 29 32 38 41 Number of Bids 11 13 15 16 18 Step 3 of 3 Calculate the coefficient of determination r Round your answer to three decimal places Copy Data

se the probability distribution or histogram to find the a mean b variance c standard deviation and d expected value of the probability distribution and e interpret the results The histogram shows the distribution of household izes in country A for a recent year a The mean is 2 392 Type an integer or a decimal Do not round b The variance is 1 68 Round to two decimal places as needed c The standard deviation is 1 30 Round to two decimal places as needed d The expected value is Type an integer or a decimal Do not round e Interpret your results Select all that apply A Most of the household sizes differ from the expected value by 2 or 3 people B The average household is expected to have either 1 or 2 people C Most of the household sizes differ from the expected value by 1 or 2 people The quoma AP x 0 40 0 30 0 20 0 10 0 001 0 298 0 325 2 0 155 0 151 0 05 3 4 5 Household Size

A researcher wishes to estimate the proportion of adults who have high speed Internet access What size sam should be obtained if she wishes the estimate to be within 0 05 with 99 confidence if a she uses a previous estimate of 0 48 b she does not use any prior estimates Click the icon to view the table of critical values a n Round up to the nearest integer b n Round up to the nearest integer Table of critical values Level of Confidence 1 a 100 90 95 99 Area in Each Tail 0 05 0 025 0 005 Critical Value z 1 645 1 96 2 575 X

In a survey conducted by a reputable marketing agency 251 of 1000 adults 19 years of age or older confessed to bringing and using their cell phone every trip to the bathroom confessions included texting and answering phone calls Complete parts a through f below Click here to view the standard normal distribution table page 1 Click here to view the standard normal distribution table page 2 OA The sample is all adults OB The sample is the a What is the sample in this study What is the population of interest Determine the sample in this study Select the correct choice below and if necessary fill in the answer box within your choice adults 19 years of age or older CO Type a whole number OC The sample is all adults with a cell phone OD The sample is all adults 19 years of age or older A The population is all adults OB The population is all adults with a cell phone This question 1 point s possible Determine the population of interest Select the correct choice below and if necessary fill in the answer box within your choice adults 19 years of age or older because OC The population is the Type a whole number OD The population is all adults 19 years of age or older b What is the variable of interest in this study Is it qualitative or quantitative The variable of interest is Submit quiz from a survey c Based on the results of this survey obtain a point estimate for the proportion of adults 19 years of age or older who bring their cell phone every trip to the bathroom OA It is being used to make inferences OB The sample size is large OC Its value may change depending on the individuals in the survey This variable is Round to three decimal places as needed d Explain why the point estimate found in part c is a statistic Explain why it is a random variable What is the source of variability in the random variable Why is the point estimate found in part c a statistic

x 120 n 200 Click here to view the table of critical values The lower bound is The upper bound is Round to three decimal places as needed Table of critical values of the population proportion using the given information Level of Confidence 1 a 100 90 95 99 Area in Each Tail 0 05 0 025 0 005 2 Critical Value z 1 645 1 96 2 575 X

In a survey conducted by a reputable marketing agency 251 of 1000 adults 19 years of age or older confessed to bringing and using their cell phone every trip to the bathroom confessions included texting and answering phone calls Complete parts a through f below Click here to view the standard normal distribution table page 1 Click here to view the standard normal distribution table page 2 t s possible O A The individuals selected to be in the study OB The question asked in the survey OC The sample size O D Random errors Why is the point estimate found in part c a random variable OA It is information obtained from a survey OB It is being used to make inferences OC The sample size is large O D Its value may change depending on the individuals in the survey OE Its value is based on a sample What is the source of variability in the random variable e Construct and interpret a 95 confidence interval for the population proportion of adults 19 years of age or older who bring their cell phone every trip to the bathroom Select the correct choice below and fill in any answer boxes within your choice Type integers or decimals rounded to three decimal places as needed Use ascending order OA There is a probability the proportion of adults 19 years of age or older who bring their cell phone every trip to the bathroom is between and OB We are confident the proportion of adults 19 years of age or older who bring their cell phone every trip to the bathroom is between and f What ensures that the results of this study are representative of all adults 19 years of age or older OA The large sample size OB Sampling from adults 19 years of age or older

In a survey conducted by a reputable marketing agency 278 of 1000 adults 19 years of age or older confessed to bringing and using their cell phone every trip to the bathroom confessions included texting and answering phone calls Complete parts a through f below Click here to view the standard normal distribution table page 1 Click here to view the standard normal distribution table page 2 a What is the sample in this study What is the population of interest Determine the sample in this study Select the correct choice below and if necessary fill in the answer box within your choice OA The sample is all adults 19 years of age or older B The sample is the 1000 adults 19 years of age or older Type a whole number OC The sample is all adults with a cell phone OD The sample is all adults Determine the population of interest Select the correct choice below and if necessary fill in the answer box within your choice O A The population is all adults with a cell phone OB The population is the Type a whole number OC The population is all adults 19 years of age or older The population is all adults adults 19 years of age or older

How profitable are different sectors of the stock market One way to answer such a question is to examine profit as a percentage of stockholder equity A random sample of 32 retail stocks such as Toys R Us Best Buy and Gap was studied for x profit as a percentage of stockholder equity The result was x 14 7 A random sample of 35 utility gas and electric stocks such as Boston Edison Wisconsin Energy and Texas Utilities was studied for x2 profit as a percentage of stockholder equity The result was x 11 1 Assume that o 3 1 and 3 7 a Let represent the population mean profit a percentage of stockholder equity for retail stocks and let represent the population mean profit as a percentage of stockholder equity for utility stocks Find a 95 confidence interval for Round your answers to two decimal places lower limit upper limit b Examine the confidence interval and explain what it means in the context of this problem Does the interval consist of numbers that are all positive all negative of different signs At the 95 level of confidence does it appear that the profit as a percentage of stockholder equity for retail stocks is higher than that for utility stocks Because the interval contains only positive numbers we can say that the profit as a percentage of stockholder equity is higher for retail stocks

1 In the game of roulette a player can place a 10 bet on the number 32 and have a probability of winning If the metal ball lands on 32 the player gets to keep the 10 paid to play the game and the player is awarded an additional 350 Otherwise the player is awarded nothing 38 and the casino takes the player s 10 What is the expected value of the game to the player If you played the game 1000 times how much would you expect to lose Note that the expected value is the amount on average one would expect to gain or lose each game The expected value is Round to the nearest cent as needed The player would expect to lose about Round to the nearest cent as needed

AP x Use the probability distribution or histogram to find the a mean b variance c standard deviation and d expected value of the probability distribution and e interpret the results The histogram shows the distribution of household sizes in country A for a 0 40 0 298 0 30 recent year 0 20 0 10 0 00 a The mean is 2 392 Type an integer or a decimal Do not round b The variance is Round to two decimal places as needed BOOME 0 325 0 155 0 151 0 051 Household Size 5 0 020

3 Use the probability distribution or histogram to find the a mean b variance c standard deviation and d expected value of the probability distribution and e interpret the results The histogram shows the distribution of household sizes in country A for a recent year a The mean is Type an integer or a decimal Do not round b The variance is Round to two decimal places as needed c The standard deviation is Round to two decimal places as needed d The expected value is Type an integer or a decimal Do not round e Interpret your results Select all that apply A Most of the household sizes differ from the expected value by 2 or 3 people B The average household is expected to have either 1 or 2 people C Most of the household sizes differ from the expected value by 1 or 2 people D average household is expected to have either 2 or 3 people AP X 0 40 0 30 0 20 0 10 0 00 0 298 0 325 2 0 155 0 151 0 051 3 Household Size

3 Use the probability distribution or histogram to find the a mean b variance c standard deviation and d expected value of the probability distribution and e interpret the results The histogram shows the distribution of household sizes in country A for a recent year a The mean is Type an integer or a decimal Do not round b The variance is Round to two decimal places as needed c The standard deviation is Round to two decimal places as needed d The expected value is Type an integer or a decimal Do not round e Interpret your results Select all that apply A Most of the household sizes differ from the expected value by 2 or 3 people B The average household is expected to have either 1 or 2 people C Most of the household sizes differ from the expected value by 1 or 2 people MP The average household is expected to have either 2 or 3 people AP X 0 40 0 30 0 20 0 10 0 00 0 298 0 325 0 155 0 151 0 051 0 020 Household Size

The data in the table below represents the percentage of patients who have survived after diagnosis of advanced stage breast cancer at 6 month intervals of time Time after Diagnosis years 0 5 1 1 5 2 2 5 3 3 5 Percentage Surviving 95 2 82 6 74 0 58 7 46 4 40 2 33 8 a Using a graphing utility build an exponential model from the data X y 100086 Type integers or decimals rounded to four decima places as needed

3 Use the probability distribution or histogram to find the a mean b variance c standard deviation and d expected value of the probability distribution and e interpret the results The histogram shows the distribution of household sizes in country A for a recent year a The mean is Type an integer or a decimal Do not round b The variance is Round to two decimal places as needed c The standard deviation is Round to two decimal places as needed d The expected value is Type an integer or a decimal Do not round e Interpret your results Select all that apply A Most of the household sizes differ from the expected value by 2 or 3 people B The average household is expected to have either 1 or 2 people C Most of the household sizes differ from the expected value by 1 or 2 people D The average household is expected to have either 2 or 3 people AP x 0 40 0 30 0 20 0 10 0 00 0 298 0 325 0 155 0 151 0 051 4 Household Size 0 020

1 Determine whether the random variable is discrete or continuous a The number of fish caught during a fishing tournament b The time it takes to fly from City A to City B c The number of points scored during a basketball game d The number of people with blood type A in a random sample of 20 people e The time it takes for a light bulb to burn out a Is the number of fish caught during a fishing tournament discrete or continuous OA The random variable is continuous OB The random variable is discrete b Is the time it takes to fly from City A to City B discrete or continuous OA The random variable is discrete OB The random variable is continuous c Is the number of points scored during a basketball game discrete or continuous OA The random variable is discrete OB The random variable is continuous d Is the number of people with blood type A in a random sample of 20 people discrete or continuous OA The random variable is discrete OB The random variable is continuous e Is the time it takes for a light bulb to burn out discrete or continuous OA The random variable is continuous OB The random variablo in dir

A random sample of 16 adult male wolves from the Canadian Northwest Territories gave an average weight x 99 lb with estimated sample standard deviation s 6 7 lb Another sample of 26 adult male wolves from Alaska gave an average weight x 89 lb with estimated sample standard deviation s 7 1 lb A USE SALT a Let represent the population mean weight of adult male wolves from the Northwest Territories and let u represent the population mean weight of adult male wolves from Alaska Find a 75 confidence interval for 2 Round your answers to one decimal place lower limit upper limit

A government s congress has 855 members of which 169 are women An alien lands near the congress building a treats the members of congress as as a random sample of the human race He reports to his superiors that a 95 confidence interval for the proportion of the human race that is female has a lower bound of 0 171 and an upper bound of 0 225 What is wrong with the alien s approach to estimating the proportion of the human race that is female Choose the correct answer below O A The confidence level is too high OB The sample size is more than 5 of the population size OC The sample size is too small OD The sample is not a simple random sample

Katrina wants to estimate the proportion of adults who read at least 10 books last year To do so she obtains a simple random sample of 100 adults and constructs a 95 confidence interval Matthew also wants to estimate the proportion of adults who read at least 10 books last year He obtains a simple random sample of 400 adults and constructs a 99 confidence interval Assuming both Katrina and Matthew obtained the same point estimate whose estimate will have the smaller margin of error Justify your answer Whose estimate will have the smaller margin of error and why O A Katrina s estimate will have the smaller margin of error because the sample size is smaller and the level of confidence is lower OB Matthew s estimate will have the smaller margin of error because the larger sample size more than compensates for the higher level of confidence OC Matthew s estimate will have the smaller margin of error because the sample size is larger and the level of confidence is higher OD Katrina s estimate will have the smaller margin of error because the lower level of confidence more than compensates for the smaller sample size

Fill in the blanks to complete the sentences below a As the number of samples increases the proportion of 95 confidence intervals that include the population proportion approaches b If a 95 confidence interval results in a sample proportion that does not include the population proportion then the sample proportion is more than standard errors from the population proportion This is a reading assessment question Be certain of your answer because you only get one attempt on this question a As the number of samples increases the proportion of 95 confidence intervals that include the population proportion approaches 0 99 1 0 05

One environmental group did a study of recycling habits in a California community It found that 72 of the aluminum cans sold in the area were recycled Use the normal approximation Round your answers to four decimal places a If 392 cans are sold today what is the probability that 300 or more will be recycled b of the 392 cans sold what is the probability that between 260 and 300 will be recycled

A new muscle relaxant is available Researchers from the firm developing the relaxant have done studies that indicate that the time lapse between administration of the drug and beginning effects of the drug is normally distributed with mean 38 minutes and standard deviation o 5 minutes a The drug is administered to one patient selected at random What is the probability that the time it takes to go into effect is 35 minutes or less Round your answer to four decimal places b The drug is administered to a random sample of 10 patients What is the probability that the average time before it is effective for all 10 patients is 35 minutes or less Round your answer to four decimal places c Comment on the differences of the results in parts a and b The probability in part b is the same as the probability in part a because the mean smaller for the x distribution