Statistics Questions

In a survey conducted by the Gallup Organization 1100 adult Americans were asked how many hours they worked in the previous week Based on the results a 95 confidence interval for the mean number of hours worked had a lowe bound of 42 7 and an upper bound of 44 5 Provide two recommendations for decreasing the margin of error of the interval Select the two recommendations that would decrease the margin of error of the interval A Increase the sample size B Use fewer degrees of freedom C Decrease the sample size D Decrease the standard deviation of hours worked E Decrease the confidence level F Increase the confidence level

lifetime is 16 years with a standard deviation of 2 years a If you bought one such car today what is the chance that your car will only last for up to 14 years b If your friend had a car of this brand for 14 years already what is the chance that he she has to buy a new car in seven years c If a company bought 7 such cars what is the probability that exactly two of them will last between 12 and 20 years d If the manufacturer want to offer a warrantee that is as attractive as possible and at the same time they don t want to refund more than 0 5 of customers how long the warranty should be

hard copy eBook eBook eBook eBook ebook eBook eBook eBook eBook hard copy hard copy hard copy eBook eBook eBook eBook hard copy eBook eBook eBook eBook hard copy O Decrease the sample size O Decrease the level of confidence O Increase the level of confidence hard copy eBook hard copy hard copy eBook eBook Determine the point estimate and the sample standard deviation s Round the sample proportion to four decimal places and round the standard deviation to six decimal places if necessary p S6 Using a 96 confidence level determine the margin of error E and a confidence interval for the proportion of all students at the college who work prefer eBooks over printed textbooks Report the confidence interval using interval notation Report the solutions in percent form rounded to two decimal places if necessary The margin of error is given by E A 96 confidence interval is given by The margin of error for this confidence interval is quite large What is the best way for the bookstore to achieve a confidence interval with a smaller margin of error

A researcher wishes to estimate the proportion of adults who have high speed Internet access What size sample should be obtained if she wishes the estimate to be within 0 02 with 99 confidence if a she uses a previous estimate of 0 38 b she does not use any prior estimates Click the icon to view the table of critical values a n 3905 Round up to the nearest integer b n Round up to the nearest integer

In a survey of 2075 adults in a certain country conducted during a period of economic uncertainty 61 thought that wages paid to workers in industry were too low The margin of error was 3 percentage points with 95 confidence For parts a through d below which represent a reasonable interpretation of the survey results For those that are not reasonable explain the flaw Is the interpretation reasonable A The interpretation is reasonable OB The interpretation is flawed The interpretation provides no interval about the population proportion OC The interpretation is flawed The interpretation suggests that this interval sets the standard for all the other intervals which is not true OD The interpretation is flawed The interpretation indicates that the level of confidence is varying d In 95 of samples of adults in the country during the period of economic uncertainty the proportion who believed wages paid to workers in industry were too low is between 0 58 and 0 64 Is the interpretation reasonable OA The interpretation is reasonable OB The interpretation is flawed The interpretation provides no interval about the population proportion OC The interpretation is flawed The interpretation suggests that this interval sets the standard for all the other intervals which is not true OD The interpretation is flawed The interpretation indicates that the level of confidence is varying

orrelation Fifty four wild bears were anesthetized and then their weights and chest sizes were measured and listed in a data set Results are shown in the accompanying display Is there sufficient evidence to support the claim that there is a linear correlation between the weights of bears and their chest sizes When measuring an anesthetized bear is it easier to measure chest size than weight If so does it appear that a measured chest size can be used to predict the weight Use a significance level of a 0 05 H p Type integers or decimals Do not round Identify the correlation coefficient r r 0 953 Round to three decimal places as needed Identify the critical value s Round to three decimal places as needed OA There are two critical values at r OB There is one critical value at r Correlation Results Correlation coeff r 0 953104 0 2680855 Critical r P value two tailed 0 000

Fill in the blank to complete the sentence below If the normality requirement is not satisfied that is np 1 p is not at least 10 then a 95 confidence interval about the population proportion will include the population proportion in 95 of the intervals This is a reading assessment question Be certain of your answer because you only get one attempt on this question If the normality requirement is not satisfied that is np 1 p is not at least 10 then a 95 confidence interval about the population proportion will include the population proportion in 95 of the intervals exactly more than

A group conducted a poll of 2045 likely voters just prior to an election The results of the survey indicated that candidate A would receive 49 of the popular vote and candidate B would receive 48 of the popular vote The margin of error was reported to be 3 The group reported that the race was too close to call Use the concept of a confidence interval to explain what this means What does it mean to say the race was too close to call OA The margin of error suggests candidate A may receive between 46 and 52 of the popular vote and candidate B may receive between 45 and 51 of the popular vote Because the poll estimates overlap when accounting for margin of error the poll cannot predict the winner OB Since the poll results do not show that one of the candidates has more than 50 of the popular vote the poll cannot predict the winner OC Since the difference between the percentages of the popular vote for the candidates is less than the 3 of voters that are undecided the poll cannot predict the winner OD Since the estimated proportions depend on the level of confidence the candidate predicted to receive the greater percentage of the popular vote changes for different levels of confidence so the poll cannot predict the winner

plain what 90 confidence means in a 90 confidence interval hat does 90 confidence mean in a 90 confidence interval A The probability that the value of the parameter lies between the lower and upper bounds of the interval is The probability that it does not is 10 O B The value of the parameter lies within 90 of a standard deviation of the estimate O C If 100 different confidence intervals are constructed each based on a different sample of size n from the same population then we expect 90 of the intervals to include the parameter and 10 to not include the parameter D The confidence interval includes 90 of all possible values for the parameter

mplete the statement below is the value of a statistic that estimates the value of a parameter confidence level confidence interval point estimate critical value

X y 10 9 13 8 8 13 13 8 75 9 8 76 11 9 26 Click here to view a table of critical values for the correlation coefficient 14 8 09 6 6 13 4 3 11 OA The scatterplot does not reveal a distinct pattern OB The scatterplot reveals a distinct pattern that is a straight line pattern with positive slope C The scatterplot reveals a distinct pattern that is not a straight line pattern D The scatterplot reveals a distinct pattern that is a straight line pattern with negative slope 12 9 13 7 7 27 B There is insufficient evidence to support the claim of a linear correlation between the two variables C There is sufficient evidence to support the claim of a nonlinear correlation between the two variables OD There is insufficient evidence to support the claim of a nonlinear correlation between the two variables c Identify the feature of the data that would be missed if part b was completed without constructing the scatterplat Choose the correct answer below

The first statistics exam had a mean of 74 and a standard deviation of 10 points the second had a mean of 83 and a standard deviation of 5 points Anna scored a 83 on both tests Megan scored 90 on the first exam and 76 on the second They both totaled 166 points on the two exams but Anna claims that her total is better Explain which is greater than Megan s total of The total of Anna s z scores is Round to one decimal place as needed COL

a Using the pairs of values for all 10 points find the equation of the regression line b After removing the point with coordinates 1 2 use the pairs of values for the remaining 9 points and find the equation of the regression line c Compare the results from parts a and b a What is the equation of the regression line for all 10 points y 2 766 0 766 x Round to three decimal places as needed b What is the equation of the regression line for the set of 9 points Round to three decimal places as needed y 10 8 6 4 02 4 6 8 10

Refer to the accompanying scatterplot a Examine the pattern of all 10 points and subjectively determine whether there appears to be a strong correlation between x and y b Find the value of the correlation coefficient r and determine whether there is a linear correlation c Remove the point 10 with coordinates 1 10 and find the correlation coefficient r and determine whether there is a linear correlation d What do you conclude about the possible effect from a single pair of values Click here to view a table of critical values for the correlation coefficient a Do the data points appear to have a strong linear correlation No Yes b What is the value of the correlation coefficient for all 10 data points Simplify your answer Round to three decimal places as needed r COFF

The Okeechobee County Health Department needs to estimate the proportion of all children in the county aged 19 35 months that are completely up to date with all state recommended immunizations The Okeechobee County Health Department found that 76 of a random sample of children in the county aged 19 35 months were completely up to date with all state recommended immunizations Find three different confidence intervals one with sample size 285 one with sample size 454 and one with sample size 631 Assume that 76 of the children each sample are completely up to date with all state recommended immunizations Observe how the sample size affects the margin of error and subsequently the width of each interval Report confidence interval solutions using interval notation Report all solutions in percent form rounded to two decimal places if necessary When n 285 the margin of error for a 90 confidence interval is given by When n 285 a 90 confidence interval is given by When n 454 the margin of error for a 90 confidence interval is given by When n 454 a 90 confidence interval is given by When n 631 the margin of error for a 90 confidence interval is given by When n 631 a 90 confidence interval is given by If the sample size is increased leaving all other characteristics constant the margin of error of the confidence interval will Select an answer If the sample size is increased leaving all other characteristics constant the width of the confidence interval will Select an answer

A normal resting heart rate for adults ranges from about 60 to 100 beats per minute BPM A doctor would like to estimate the average heart rate for one of her patients The doctor instructs her patient to measure their resting heart rate twice a day for one week The measurements are listed below Assume that the distribution of all heart rate measurements of this patient is approximately normally distributed X 89 07 8 4 141 92 81 95 2232 A 95 confidence interval is given by 94 91 89 89 Determine the point estimate and the sample standard deviation s Round the solutions to four decimal places if necessary 88 88 88 93 90 88 81 Using a 95 confidence level determine the margin of error E and a confidence interval for the average resting heart rate of this patient Report the confidence interval using interval notation Round solutions to two decimal places if necessary The margin of error is given by E

Determine the correct graph for the following equation x 3 4 y 2 9 De 1

A world record was set in a given year for the longest run on an ungaffed fair roulette wheel The number 8 appeared 6 times in a row What is the probability of the occurrence of this event Assume that there are 38 equally likely outcomes consisting of the number 1 36 0 and 00 If you enter your answer in scientific notation round the decimal value to two decimal places Use equivalent rounding if you do not enter your answer in scientific notation

1 Given the function represented by the following graph Note The corners are at 1 0 2 0 4 and 6 0 0 6 0 4 0 2 0 0 2 2 3 y f x a 3 pts Verify that it is a probability density function 4 L O 5 6

K A scientist claims that pneumonia causes weight loss in mice The table shows the weights in grams of six mice before infection and two days after infection At a 0 05 is there enough evidence to support the scientist s claim Assume the samples are random and dependent and the population is normally distributed Complete parts a through e below Mouse Weight before Weight after a Hd V D Ho Hd 0 H H0 t 1 2 3 4 5 60 23 3 20 5 23 1 21 4 20 7 22 6 22 0 19 6 22 2 21 0 19 8 21 6 b Find the critical value s and identify the rejection region s Select the correct choice below and fill in any answer boxes to complete your choice Round to three decimal places as needed A t 2 015 OB tort O C t c Calculated and sa d 0 900 Round to three decimal places as needed Calculate Sd Sd 0 290 Round to three decimal places as needed d Find the standardized test statistic t a Pd O E Ho Hdd Ha Hdd 4 Round to two decimal places as needed e Decide whether to reject or fail to reject the null hypothesis and interpret the decision in the context of the original claim adu OF Ho Hazd Ha Pa d

A professor would like to use a 98 confidence interval to estimate the mean amount of time IRSC students spend studying each week The professor knows that distribution of time spent studying each week by IRSC students is normally distributed with a standard deviation of 11 1 hours How large a sample should the professor select to ensure the confidence interval has a width of no more than 5 8 hours Round the solution up to the nearest whole number

Points 0 3 of 1 K To compare the dry braking distances from 30 to 0 miles per hour for two makes of automobiles a safety engineer conducts braking tests for 35 models of Make A and 35 models of Make B The mean braking distance for Make A is 45 feet Assume the population standard deviation is 4 5 feet The mean braking distance for Make B is 47 feet Assume the population standard deviation is 4 3 feet At a 010 can the engineer support the claim that the mean braking distances are different for the two makes of automobiles Assume the samples are random and independent and the populations are normally distributed Complete parts a through e Click here to view page 1 of the standard normal distribution table Click here to view page 2 of the standard normal distribution table A Ho H H Ha H1 H OD Ho H1 H Ha H1 H2 OA z 2 81 OC z 1 64 E z 1 64 z 1 64 OG z 2 81 z 2 81 Part 5 of 7 b Find the critical value s and identify the rejection region s The critical value s is are 1 64 1 64 Round to two decimal places as needed Use a comma to separate answers as needed What is are the rejection region s c Find the standardized test statistic z for 2 z Round to two decimal places as needed OB Ho H H Ha H1 H2 OE Ho H H Ha 11 12 ACCESS B z 2 58 z 2 58 D z 258 OF Z 2 58 OH z 1 96 z 1 96 Ho kg 12 H 14 52 OF Ho H H H H 2 Save

Part 1 of 2 a Find the critical value s assuming that the population variances are equal Use the t distribution table to find the critical value s for the indicated alternative hypotheses level of significance a and sample sizes n and n Assume that the samples are independent normal and random Answer parts a and b Ha 1 0 20 n 18 n 8 XXX O Points 0 of 1 Type an integer or decimal rounded to three decimal places as needed Use a comma to separate answers as needed Save

A researcher claims that the stomachs of blue crabs from Location A contain more fish than the stomachs of blue crabs from Location B The stomach contents of a sample of 15 blue crabs from Locatic contain a mean of 191 milligrams of fish and a standard deviation of 39 milligrams The stomach contents of a sample of 11 blue crabs from Location B contain a mean of 189 milligrams of fish and a st deviation of 45 milligrams At a 0 05 can you support the researcher s claim Assume the population variances are equal Complete parts a through d below a Identify the null and alternative hypotheses Choose the correct answer below OA Ho H H 0 Ha H 0 OC Ho H 1 0 Ha 1 0 C OB Ho H1 H 0 Ha H1 H 0 OD Ho H1 H 0 Ha H1 H 0

To construct a confidence interval for the difference between two population means H use the formula shown below when both population standard deviations are known and either both populations are normally distributed or both n 30 and n 30 Also the samples must be randomly selected and independent 0 0 2 0 0 x x H1 H X X Zc n n n n The descriptive statistics for the annual salaries from a random sample of microbiologists from two regions are shown below Construct a 95 confidence interval for the difference between the mean annual salaries X 107 170 n 37 and 8620 x 85 740 n 43 and 8595 Zc Complete the 95 confidence interval for H below H1 H S Round to the nearest dollar as needed

Determine the alternative hypothesis Ha Hy H2 Determine the standardized test statistic Z 2 93 Round to two decimal places as needed Part 3 of 4 Determine the P value P value Round to three decimal places as needed HW Score 48 53 11 65 of 24 points Points 0 25 of 1 Test the claim about the difference between two population means and 2 at the level of significance a Assume the samples are random and independent and the populations are normally distributed Claim 0 01 Population parameters o 3 4 0 1 5 Sample statistics x 16 n 30 x 18 n 28 Save

A poll of 991 U S adults split the sample into four age groups ages 18 29 30 49 50 64 and 65 In the youngest age group 65 said that they thought the U S was ready for a woman president as opposed to 32 who said no the country was not ready 3 were undecided The sample included 248 18 to 29 year olds a Do you expect the 95 confidence interval for the true proportion of all 18 to 29 year olds who think the U S is ready for a woman president to be wider or narrower than the 95 confidence interval for the true proportion of all U S adults b Construct a 95 confidence interval for the true proportion of all 18 to 29 year olds who believe the U S is ready for a woman president XL a The 95 confidence interval for the true proportion of 18 to 29 year olds who think the U S is ready for a woman president will be about the true proportion of all U S adults who think this b The 95 confidence interval is Round to one decimal place as needed twice as wide as the 95 confidence interval for

K A humane society claims that less than 70 of households in a certain country own a pet In a random sample of 700 households in that country 476 say they own a pet At a 0 10 is there enough evidence to support the society s claim Complete parts a through c bela a Identify the claim and state Ho and Ha Identify the claim in this scenario Select the correct choice below and fill in the answer box to complete your choice Type an integer or a decimal Do not round OA Less than of households in the country own a pet of households in the country own a pet OB More than OC 68 of households in the country own a pet OD The percentage households in the country that own a pet is not OA Ho P Let p be the population proportion of successes where a success is a household in the country that owns a pet State Ho and H Select the correct choice below and fill in the answer boxes to complete your choice Round to two decimal places as needed H p OD Ho P Ha pa b Use technology to find the P value Identify the standardized test statistic z Round to two decimal places as needed Identify the P value the pull hypothesis There enough evidence to B Ho pz 0 70 Hap 0 70 P Round to three decimal places as needed c Decide whether to reject or fail to reject the null hypothesis and d interpret the decision in the context of the original claim OE Ho Ps H p CDD the society s claim OC Ho PF H p OF Ho p Ha ps

A college Like the propor students that work full time while going to school A researcher at the college found that 183 students out of a random sample of 445 students worked full time while going to school Determine the point estimate p and the sample standard deviation Sp Round the sample proportion to four decimal places and round the standard deviation to six decimal places if necessary 2 Using a 95 confidence level determine the margin of error E and a confidence interval for the proportion of all students at the college who work full time while going to school Report the confidence interval using interval notation Round solutions to four decimal places if necessary The margin of error is given by E A 95 confidence interval is given by

K The dean of a university estimates that the mean number of classroom hours per week for full time faculty is 11 0 As a member of the student council you want to test this claim A random sample of the number of classroom hours for eight full time faculty for one week is shown in the table below At a 0 05 can you reject the dean s claim Complete parts a through d below Assume the population is normally distributed 12 7 8 3 12 7 6 7 a Write the claim mathematically and identify Ho and H Which of the following correctly states Ho and H OA Ho 11 0 H 11 0 OD Ho 2 11 0 H p 11 0 b Use technology to find the P value P Round to three decimal places as needed c Decide whether to reject or fail to reject the null hypothesis Which of the following is correct OB Ho 11 0 H us11 0 OE Ho p 11 0 H 211 0 OA Reject Ho because the P value is greater than the significance level OB Fail to reject Ho because the P value is less than the significance level OC Fall to reject Ho because the P value is greater than the significance level OD Reject Ho because the P value is less than the significance level d Interpret the decision in the context of the original claim O A At the 5 level of significance there is sufficient evidence to reject the claim that the mean number of classroom hours per week for full time faculty is 11 0 OC At the 5 level of significance there is not sufficient evidence to reject the claim that the mean number of classroom hours per week for full time faculty is 11 0 7 7 11 3 OC Ho 11 0 H p 11 0 OF Ho H 11 0 H 11 0 13 2 8 4 O B At the 5 level of significance there is sufficient evidence to reject the claim that the mean number of classroom hours per week for full time faculty is greater than 11 0 OD At the 5 level of significance there is not sufficient evidence to reject the claim that the mean number of classroom hours per week for full time faculty is less than 11 0

Part 1 of 4 An economist at the Florida Department of Labor and Employment needs to estimate the unemployment rate in Okeechobee county The economist found that 2 31 of a random sample of 678 county residents were unemployed Find three different confidence intervals for the true proportion of Okeechobee county residents who are unemployed Calculate one confidence interval with a 95 confidence level one with a 97 confidence level and one with a 98 confidence level Notice how the confidence level affects the margin of error and the width of the interval Report confidence interval solutions using interval notation Express solutions in percent form rounded to two decimal places if necessary The margin of error for a 95 confidence interval is given by E A 95 confidence interval is given by

printed textbooks hard copies A random sample of 30 students was surveyed Their preferences are listed below hard copy hard copy eBook hard copy eBook hard copy hard copy eBook hard copy hard copy eBook eBook eBook eBook eBook hard copy eBook eBook hard copy eBook eBook eBook hard copy eBook eBook hard copy hard copy hard copy eBook eBook Determine the point estimate p and the sample standard deviation s Round the sample proportion to four decimal places and round the standard deviation to six decimal

An automobile manufacturer needs to estimate the average highway fuel economy miles per gallon for a new truck that will be sold starting next year A random sample of 148 trucks were tested for highway fuel economy and the sample had a mean of 28 5 miles per gallon with a standard deviation of 2 5 miles per gallon Using a 95 confidence level determine the margin of error E and a confidence interval for the average highway fuel economy of this new truck Report the confidence interval using interval notation Round solutions to two decimal places if necessary The margin of error is given by E A 95 confidence interval is given by

Suppose that the heights of adult men in the United States are normally distributed with a mean of 69 inches and a standard deviation of 3 5 inches What proportion of the adult men in the United States are at most 6 feet tall Hint 6 feet 72 inches Round your answer to at least four decimal places

Quiz for an 8 week class Construct a 90 confidence interval for with the sample statistics for mean cholesterol content of a hamburger from two fast food chains and confidence interval construction formula below Assume the populations are approximately normal with unequal variances x2 67 mg s 2 11 mg n 12 x 84 mg s 3 59 mg n 20 K Stats Confidence interval when variances are not equal x x tc H H X x tc n d f is the smaller of n 1 or n 1 Enter the endpoints of the interval H H Round to the nearest integer as needed This question 1 point s possible n

and 7 Quiz for an 8 week class K Test the claim about the difference between two population means and at the level of significance a Assume the samples are random and independent and the populations are normally distributed Claim 0 05 Assume o 0 Sample statistics x 2410 s 175 n 13 and x 2298 s 54 n 10 Identify the null and alternative hypotheses Choose the correct answer below OA Ho HH2 Ha H1 H2 OC Ho H H H H12H OE HO H 2 H P H Find the standardized test statistic t t Round to two decimal places as needed Find the P value P Round to three decimal places as needed Decide whether to reject or fail to reject the null hypothesis and interpret the decision in the context of the original claim Ho There enough evidence at the 5 level of significance to reject the claim Fail to reject Reject ACCED OB Ho Ha H1 H OD Ho 2 H H1 OF Ho H H Ha H1 H2

7 Quiz for an 8 week class K The dean of a major university claims that the mean time for students to earn a Master s degree is at most 4 4 years If a hypothesis test is performed how should you interpret a decision that fails to reject the null hypothesis OA There is not sufficient evidence to reject the claim 4 4 OB There is sufficient evidence to support the claim us 4 4 OC There is not sufficient evidence to support the claim 4 4 OD There is sufficient evidence to reject the claim us 4 4 This question GREES

K For the statement below write the claim as a mathematical statement State the null and alternative hypotheses and identify which represents the claim An amusement park claims that the mean daily attendence at the park is at least 20 000 people Write the claim as a mathematical statement OA 20 000 OD 20 000 Choose the correct null and alternative hypotheses below OA Ho 20 000 Ha 220 000 OD Ho 20 000 Hus 20 000 Identify which is the claim A The alternative hypothesis H H 20 000 is the claim OB The null hypothesis Ho 220 000 is the claim OC The alternative hypothesis H 20 000 is the claim OD The alternative hypothesis H 20 000 is the claim OE The null hypothesis Ho u 20 000 is the claim OF The null hypothesis Ho p 20 000 is the claim OB H 20 000 OE 220 000 OB Ho 20 000 H 20 000 OE Ho 20 000 Ha 20 000 www OC p 20 000 OF 20 000 OC Ho 20 000 Ha 20 000 OF Hou220 000 H 20 000

K Find the critical value s for the type of t test with level of significance a and sample size n H 20 x 0 10 n 20 OA 1 729 OB 2 093 OC 2 861 OD 1 328 4

7 Quiz for an 8 week class K Use the calculator displays to the right to make a decision to reject or fail to reject the null hypothesis at a significance level of a 0 10 Choose the correct answer below OA Since the P value is less than a reject the null hypothesis OB Since the P value is greater than a reject the null hypothesis OC Since the P value is greater than a fail to reject the null hypothesis OD Since the P value is less than a fail to reject the null hypothesis This question 1 poin s possible Z Test Inpt Data Stats Ho 70 5 25 x67 75 n 40 HHo Ho H Calculate Draw

A marine biologist would like to estimate the mean weight of all redfish on the Treasure Coast using a 95 confidence interval The standard deviation of the weights of all redfish on the Treasure Coast is known to be 8 3 pounds How large a sample of redfish should the marine biologist select so that the estimate is within 0 67 pounds of the true population mean Round the solution up to the nearest whole number n

K Identify the type I error and the type Il error for a hypothesis test of the indicated claim The percentage of adults who have a job is greater than 88 Identify the type I error Choose the correct answer below OA Fail to reject the null hypothesis that the percentage of adults who have a job is greater than 88 when it is actually false OB Fail to reject the null hypothesis that the percentage of adults who have a job is less than or equal to 88 when it is actually false OC Reject the null hypothesis that the percentage of adults who have a job is less than or equal to 88 when it is actually true OD Reject the null hypothesis that the percentage of adults who have a job is greater than 88 when it is actually true Identify the type Il error Choose the correct answer below OA Fail to reject the null hypothesis that the percentage of adults who have a job is less than or equal to 88 when it is actually false OB Reject the null hypothesis that the percentage of adults who have a job is less than or equal to 88 when it is actually true OC Fail to reject the null hypothesis that the percentage of adults who have a job is greater than 88 when it is actually false OD Reject the null hypothesis that the percentage of adults who have a job is greater than 88 when it is actually true

Quiz for an 8 week class As part of a Master s thesis project a mathematics teacher is interested in the effects of two different teaching methods on mathematics achievement She randomly chooses one class of students to learn an algebraic concept using traditional methods and another class of students to learn the same algebraic concept using manipulatives The teacher then compares their test scores Determine whether the samples are dependent or independent O independent O dependent

For which confidence interval for the difference in the means 2 would you reject the null hypothesis OA 2209 0 209 OB 1 968 1561 OC 2001 1 873 OD 1673 1 892 CHE

This question 1 point s possible K A humane society claims that less than 70 of households in a certain country own a pet In a random sample of 700 households in that country 476 say they own a pet At a 0 10 is there enough evidence to support the society s claim Complete parts a through c below a Identify the claim and state Ho and Ha Identify the claim in this scenario Select the correct choice below and fill in the answer box to complete your choice Type an integer or a decimal Do not round O A Less than of households in the country own a pet OB More than of households in the country own a pet O C of households in the country own a pet OD The percentage households in the country that own a pet is not OA Ho P Ha p Let p be the population proportion of successes where a success is a household in the country that owns a pet State Ho and H Select the correct choice below and fill in the answer boxes to complete your choice Round to two decimal places as needed OD Ho P Ha p b Use technology to find the P value Identify the standardized test statistic www OB Ho p2 Ha p OE Ho Ps Ha p OC Ho P Ha p Submit quiz OF Ho P Ha ps W

In a memory test the test subjects are given a large number and are asked to memorize it Historical records show that 75 of test subjects pass the test To pass the test a subject must exactly repeat all the digits in the number after two hours A random sample of 300 people to take the memory test is going to be chosen Let p be the proportion of people in the sample who pass the test Answer the following If necessary consult a list of formulas a Find the mean of p 0 b Find the standard deviation of p c Compute an approximation for P p 0 78 which is the probability that fewer than 78 of the people in the sample pass the test Round your answer to four decimal places 0

7 Quiz for an 8 week class K The dean of a university estimates that the mean number of classroom hours per week for full time faculty is 11 0 As a member of the student council you want to test this claim A random sample of the number of classroom hours for eight full time faculty for one week is shown in the table below At a 0 05 can you reject the dean s claim Complete parts a through d below Assume the population is normally distributed 12 7 83 12 7 6 7 a Write the claim mathematically and identify Ho and H Which of the following correctly states Ho and H OA Ho us11 0 H 11 0 OD Ho u211 0 H p 11 0 b Use technology to find the P value P Round to three decimal places as needed c Decide whether to reject or fail to reject the null hypothesis Which of the following is correct OB Ho 11 0 H 11 0 OE Ho 11 0 H 211 0 OA Reject Ho because the P value is greater than the significance level OB Fail to reject Ho because the P value is less than the significance level OC Fail to reject Ho because the P value is greater than the significance level OD Reject Ho because the P value is less than the significance level d Interpret the decision in the context of the original claim OA At the 5 level of significance there is sufficient evidence to reject the claim that the mean number of classroom hours per week for full time faculty is 11 0 OC At the 5 level of significance there is not sufficient evidence to reject the claim that the mean number of classroom hours per week for full time faculty is 11 0 7 7 This ques 11 3 OC Ho 11 0 H p 11 0 OF Ho 11 0 H 11 0 13 2 8 40 for full time faculty is greater than 11 0 OB At the 5 level of significance there is sufficient evidence to reject the claim that the mean number of classroom hours per week OD At the 5 level of significance there is not sufficient evidence to reject the claim that the mean number of classroom hours per week for full time faculty is less than 11 0

K Explain how to decide when a normal distribution can be used to approximate a binomial distribution Choose the correct answer below OA If np 5 and nq 5 the normal distribution can be used B If np 0 and nq 0 the normal distribution can be used O C If np 5 and nq 5 the normal distribution can be used OD If np 5 and nq 25 the normal distribution can be used

A biologist needs to estimate the weight of all spiny lobsters on the Treasure Coast To achieve this the biologist collects a random sample of 20 spiny lobsters The weights of each lobster in the sample are given below Assume that the weights of all spiny lobsters on the Treasure Coast are normally distributed S 6 1 5 9 7 8 1 7 7 8 9 9 7 8 5 7 1 6 8 6 6 Determine the point estimate and the sample standard deviation s Round the solutions to four decimal places if necessary 6 3 7 8 6 2 7 4 5 1 5 7 6 2 5 3 Using a 95 confidence level determine the margin of error E and a confidence interval for the average weight of a spiny lobster on the Treasure Coast Report the confidence interval using interval notation Round solutions to two decimal places if necessary The margin of error is given by E A 95 confidence interval is given by

K The statement represents a claim Write its complement and state which is Ho and which is HA p 9 7 OA Ho 9 7 H p 9 7 claim OB Ho p29 7 claim Ha 9 7 OC Ho 9 7 Ha p 9 7 claim O D Ho p 9 7 claim H 9 7