Statistics Questions

Identify the population and the sample Describe the sample data set A survey of 138 law firms in a country found that the average hourly billing rate for partners was 632 Identify the population Choose the correct answer below the law firms that were surveyed all law firms in the country all people in the country O O O O all partners Identify the sample Choose the correct answer below O all partners O all people in the country Oall law firms in the country O the law firms that were surveyed Describe the sample data set Choose the correct answer below O A Charging an average of 632 per hour OB The 138 law firms OC The average hourly billing rate for partners of 138 law firms was 632 OD Partners of 138 law firms were billed exactly 632 per hour

etermine whether the statement is true or false If it is false rewrite it as a true statement ore types of calculations can be performed with data at the nominal level than with data at the interval level hoose the correct answer below www O A False The same types of calculations can be performed with data at the nominal level and with data at the int O B True OC False More types of calculations can be performed with data at the interval level than with data at the nomina

The following table gives the number of fatal work injuries categorized by cause from 2015 in a certain country Cause Number of Fatalities 2462 740 749 823 402 Transportation accidents Assaults and violent acts Contacts with objects and equipment Falls Exposure to harmful substances or environments Fires and explosions Other Find the probability that a randomly chosen work fatality had the following cause Assaults and violent acts There were a total of fatal work injuries The probability is Round to four decimal places as needed 140 11

1 Calculate the mean median and mode for Data Set A Then tell me about skewness for the data set DATA SET A 100 35 40

2 Calculate all appropriate measures of variation for the interval data represented in Data Set A Make sure you show all of your work and demonstrate the use of the formulas DATA SET A 5

The revenue function R x and the cost function Cix for a particular product are given These functions are valid only for the specified range of values Find the number of units that must be produced to break even Rix 200x 2x C x x 45x 5250 0x100 The manufacturer must produce units to break even

You plan to take out a 30 year fixed rate mortgage for 125 000 Let P r be your monthly payment if the interest rate is 1 per year compounded monthly Interpret the equations a P 7 831 63 and 0 P 7 83 95 a Interpret P 7 831 63 Select the correct answer below A If the interest rate on the mortgage is 8 the monthly payment will be 831 63 B If the interest rate on the mortgage is 7 the monthly payment will be 83 95 C If the interest rate on the mortgage is 8 the monthly payment will be 83 95 D If the interest rate on the mortgage is 7 the monthly payment will be 831 63 b Interpret P 7 83 95 Select the correct answer below A If the interest rate increases from 7 to 8 the monthly payment will increase by approximately 83 95 B If the interest rate decreases from 8 to 7 the monthly payment will increase by approximately 831 63 OC If the interest rate increases from 7 to 8 the monthly payment will decrease by approximately 83 95 OD If the interest rate decreases from 8 to 7 the monthly payment will be approximately 831 63 O

Assume that two marbles are drawn without replacement from a box with 1 blue 3 white 2 green and 2 red marbles Find the probability of the indicated resul The second marble is blue given that the first marble is white O O 18 B C 35 4 3 D 7

The table gives estimates of the world population in millions from 1750 to 2000 Round your answers to the nearest million Population millions Year 1750 1800 1850 1900 1950 2000 790 980 1260 Enhanced Feedback 1650 2560 6080 a Use the exponential model and the population figures for 1750 and 1800 to predict the world population in millions of people in 1900 and 1950 Compare with the actual figures 1900 1507 99 million people million people 1950 1870 63 b Use the exponential model and the population figures for 1800 and 1850 to predict the world population in millions of people in 1950 Compare with the actual population 2160 7142 million people c Use the exponential model and the population figures for 1900 and 1950 to predict the world population in millions of people in 2000 Compare with the actual population 3971 8750 million people BOY kt where R in the initial value of the population and k is the growth rate Keep in mind that t is the difference

What is a cross sectional study What is a case control study Which is the superior observational study Why look back in time or require the researcher to look at existing records What is a case control study Choose the correct answer below O A Case control studies are observational studies that collect information about individuals at a specific point in time or over a very short period of time B Case control studies are observational studies that are retrospective meaning that they require individuals to look back in time or require the researcher to look at existing records OC Case control studies first identify a group of individuals to participate in the study These individuals are then observed over a period of time Over this period of time characteristics about the individual are recorded O D Case control studies are a list of all individuals in a population along with certain characteristics of each individual Which is the superior observational study Why Choose the correct answer below O A Case control studies are always the superior observational study because they are relatively inexpensive to conduct and can be done relatively quickly OB Cross sectional studies are always the superior observational study because they are cheap and quick to do OC Neither study is always the superior to the other Both have advantages and disadvantages that depend on the situation

Click on icon to view the data Complete the frequency distribution below Frequency Length in 0 470 Type integers or decimals rounded to the nearest thousandth as needed Data table Screw Lengths inches 0 487 0 508 0 498 0 495 0 484 0 493 0 503 0 475 0 501 0 501 D X

Which graph below corresponds to the following hypothesis test Ho 25 9 H 5 9 Select the correct answer below O 5 9 5 9

Jonathan a college business student wants to study how many pages of notes fellow classmates took during a semester for a finance class Past data reveals that pages of notes for a finance college class has a mean of 95 with standard deviation 25 pages He plans to take a random sample of 30 such college students and will calculate the mean pages of notes they take to compare to the known pages of notes students take for a finance college class For these values the mean and standard deviation of the sampling distribution of sample means for a sample of size 30 are 95 and 4 6 25 30 What is the probability that the sample mean for a sample of size 30 will be at least 99 You may use a calculator or the portion of the z table given below Round your answer to the nearest percent Z 0 5 0 6 0 7 0 8 0 9 1 0 1 1 1 2 0 00 0 01 0 02 0 03 0 06 0 07 0 08 0 05 0 7088 0 7123 0 6915 0 6950 0 6985 0 7019 0 7157 0 7190 0 04 0 7054 0 7389 0 7704 0 7734 0 7764 0 7257 0 7291 0 7324 0 7357 0 7422 0 7454 0 7486 0 7517 0 7580 0 7611 0 7642 0 7673 0 7794 0 7823 0 7881 0 7910 0 7939 0 7967 0 8078 0 8106 0 7995 0 8023 0 8051 0 8289 0 8159 0 8186 0 8212 0 8238 0 8264 0 8315 0 8340 0 8365 0 8413 0 8438 0 8461 0 8485 0 8508 0 8531 0 8554 0 8577 0 8599 0 8643 0 8665 0 8686 0 8708 0 8729 0 8749 0 8770 0 8790 0 8810 0 8849 0 8869 0 8888 0 8907 0 8925 0 8944 0 8962 0 8980 0 8997 0 09 0 7224 0 7549 0 7852 0 8133 0 8389 0 8621 0 8830 0 9015

What is a cross sectional study Choose the correct answer below O A Cross sectional studies are observational studies that collect information about individuals at a specific point in time or over a very short period of time O B Cross sectional studies first identify a group of individuals to participate in the study These individuals are then observed over a period of time Over this period of time characteristics about the individual are recorded OC Cross sectional studies are a list of all individuals in a population along with certain characteristics of each individual O D Cross sectional studies are observational studies that are retrospective meaning that they require individuals to look back in time or require the researcher to look at existing records What is a case control study Choose the correct answer below O A Case control studies are observational studies that collect information about individuals at a specific point in time or over a very short period of time O B Case control studies are observational studies that are retrospective meaning that they require individuals to look back in time or require the researcher to look at existing records OC Case control studies first identify a group of individuals to participate in the study These individuals are then observed over a period of time Over this period of time characteristics about the individual are recorded O D Case control studies are a list of all individuals in a population along with certain characteristics of each

High and low temperatures in degrees Fahrenheit for a particular city over the course of a year Find the mean and median of the low temperat Click here to view the monthly high and low temperatures The mean low temperature is F Type an integer or decimal rounded to the nearest tenth as needed The median low temperature is F Type an integer or decimal rounded to the nearest tenth as needed Monthly High and Low Temperatures Month January February March April May High Low 49 29 52 31 61 41 70 49 2888288 77 56 June July August September 80 October November 60 December 52 83 66 89 29885393 85 70 69 48 42 34

The graph on the right gives the annual per person retail availability of beef chicken and pork in pounds from 2007 to 2012 In what year was annual availability of chicken the lowest The annual availability of chicken was the lowest in the year Pounds 25568637 70 60 50 45 40 Submit LOST 2007 2008 2009 2010 2011 2012 Year ON

3 A dietitian claims that there is difference between male and female who are trying to avoid trans fats in their diets She randomly selected 300 people 150 male and 150 female and found that 95 male and 120 female stated that they were trying to avoid trans fats in their diets and a What percentage of people are trying to avoid trans fat b What percentage of female are trying to avoid trans fat c What percentage of male are trying to avoid trans fat d What is the Ho null hypothesis e What is the H alternate hypothesis f Using the 1 level of significance what is the critical value and the test value g What is the p value asymptotic significance h What is your decision i At a 0 01 is there enough evidence to say proportion of male and female is different

What was the difference between the highest and lowest monthly sales in 1989 Big D Sales 1989 1990 sales Thousands of dollars 76 72 68 64 68 M056 52 48 44 48 1998 1989 4 41 42 Month C A 6000 B 8000 OC 2000 OD 4000

Respondents to a survey indicated the following categorizations pertaining to attendance at religious services There were a total of 2025 respons Number of Respondents 255 129 474 288 24 Find the probability that a randomly chosen person attends religious services with the indicated frequency in parts a through c below Attendance Never Less than once a year Once a year Several times a year Once a month Number of Respondents 755 147 317 377 160 a once a month The probability is Round to four decimal places as needed b every week The probability is Round to four decimal places as needed c nearly every week or more frequently The probability is Round to four decimal places as needed Attendance 2 3 times a month Nearly every week Every week More than once a week Don t know no answer CHE

The lost value of equipment over a period of time is called depreciation The simplest method for calculating depreciation is straight line depreciation The annual straight in depresion of an costs x dollars with a useful life of n years is D 1 n x Find the depreciation for items with the g he given c characteristics Cost is 15 966 life is 16 yr The annual straight line depreciation is approximately 997 88 per year Round to the nearest cent

Use the table which gives the total amounts of sales in millions of dollars for aerobic basketball cross training and 2005 252 walking shoes for the years 2005 2011 2006 253 Determine which type of shoe shows 2007 288 greater variation aerobic or cross training 2008 261 2009 Year Aerobic Basketball 219 2010 240 2011 269 878 964 892 718 741 721 729 Cross Training 1450 1539 1558 1632 2084 Walking 3673 4091 4197 4204 4416 2124 4256 2152 4299 Which type of shoe shows greater variation aerobic or cross training OA Aerobic shows greater variation with a standard deviation of million dollars B Cross training shows greater variation with a standard deviation of million dollars OC Aerobic and cross training have equal variances Round to one decimal place as needed

Thinking about how the tariff issue might affect your vote for major offices would you vote only for a candidate wh shares your views on tariffs or consider a candidate s position on tariffs as just one of many important factors rotated Why is it important to rotate the two choices presented in the question Which of the following is correct OA The choices need to be rotated to minimize nonresponses OB The choices need to be rotated to minimize the effect of a poorly worded question OC The choices need to be rotated to minimize interviewer error OD The choices need to be rotated to minimize response biases

uppose that a newspaper predicted that Candidate A would defeat Candidate B in a certain election They conducted oll of its subscribers with a response rate of 25 On the basis of the results the newspaper predicted that Candidate would win with 57 of the popular vote However Candidate B won the election with about 62 of the popular vote at the time of this poll most subscribers to the newspaper belonged to the party of Candidate A Name two biases that ed to this incorrect prediction Choose the correct answer below A Nonresponse bias The low response rate caused bias Response bias The way the poll was administered showed bias OB Sampling bias Using an incorrect frame led to undercoverage Nonresponse bias The low response rate caused bias OC Sampling bias Using an incorrect frame led to undercoverage Response bias The way the poll was administered showed bias

Determine whether the study depicts an observational study or an experiment Sixty college students are divided into two groups One group is exposed to rock music while studying The other is not After one week both groups are questioned about their scores on final mathematical examinations Is the study an observational study or an experiment OA The study is an experiment because the researchers control one variable to determine the effect on the response variable OB The study is an observational study because the researchers control one variable to determine the effect on response variable OC The study is an observational study because the study examines individuals in a sample but does not try to influence the response variable OD The study is an experiment because the study examines individuals in a sample but does not try to influence the variable of interest

Whether the study depicts an observational study or an experiment Professional weightlifters are randomly divided into two groups One group is given a diet of mostly protein the other is given a diet of mostly carbohydrates After 1 week each group is given a ifting test to compare strength Choose the correct description of the study OA The study is an observational study because the study examines individuals in a sample but does not try to influence the variable of interest OB The study is an experiment because the study examines individuals in a sample but does not try to influenc the variable of interest OC The study is an observational study because the researchers control one variable to determine the effect on response variable OD The study is an experiment because the researchers control one variable to determine the effect on the response variable

To determine customer opinion of their safety features Daimler Chrysler randomly selects 110 service centers during a certain week and surveys all customers visiting the service centers What type of sampling is used OA Systematic OB Stratified OC Simple random O D Cluster E Convenience

Determine whether the following statement is true or false Explain A simple random sample is always preferred because it obtains the same information as other sampling plans but requires a smaller sample size Choose the correct answer below O A False because simple random samples require a larger sample size than most other sampling methods OB True because every individual has an equal chance of selection OC False because other sampling techniques may provide more information for less cost than a simple random sample O D True because it does not require extra preparation and can return more information than the other sampling techniques

a Determine the type of bias b Suggest a remedy A newspaper article reported The famous magazine survey of more than 5 000 women aged 18 34 found about 42 percent considered themselves overweight or obese a What is the type of bias O Sampling bias O Response bias O Nonresponse bias b What is a possible remedy O Reword the question O Conduct face to face or telephone interviews Lise systematic random sampling

A quality control manager randomly selects 20 bottles of ketchup that were filled on November 9 to assess calibration of the filling machine What is the population in the study OA All bottles of ketchup produced in the plant on November 9 OB The 20 bottles of ketchup selected in the plant OC The 20 bottles of ketchup selected in the plant on November 9 O D All bottles of ketchup produced in the plant in the given year What is the sample in the study OA The 20 bottles of ketchup selected in the plant on November 9 OB The 20 bottles of ketchup selected in the plant in November OC All bottles of ketchup produced in the plant in the given year D All bottles of ketchup produced in the plant on November 9

A pharmaceutical company wants to conduct a survey of 20 individuals who have high cholesterol The company has obtained a list from primary care physicians throughout the country of 3400 individuals who are known to have high cholesterol Design a sampling method to obtain the individuals in the sample Be sure to support the choice What sampling method s is are valid Select all that apply A Group the individuals by common primary care physician For each group assign all the individuals different numbers and use a random number table to select an appropriate number of individuals B Alphabetize the list of 3400 individuals by last name and select one of the first 170 individuals at random Starting from the selected individual read down the list and select every 170th individual C Group the individuals by common primary care physician Assign each physician a different number and use a random number table to select physicians until the total number of patients of all the selected physicians is at least 20 D Select a hospital at random from a list of all of the country s hospitals Survey individuals that pass by the front desk until there are responses from 20 individuals with high cholesterol

poll is being conducted at an outlet store to obtain a sample of the population of an entire country What is the frame or this type of sampling Who would be excluded from the survey and how might this affect the results of the survey What is the frame for this type of sampling OA The frame is people who need new clothes OB The frame is people who like to shop OC The frame is people who shop at the outlet store OD The frame is the entire population of the country Who would be excluded from the survey and how might this affect the results of the survey OA Any person who does not like to shop is excluded This could result in sampling bias due to undercoverage OB Any person who does not shop at outlet stores is excluded This could result in nonresponse bias due to people not participating in the poll OC Any person who does not shop at outlet stores is excluded This could result in sampling bias due to undercoverage D There is nobody that is being excluded from the survey

Blood type AB is somewhat rare in the United States it is found in 4 of the general population It is particularly useful for plasma transfusions because this plasma can be accepted by individuals with all blood types The plasma is the liquid part of the blood once all cells are removed You count the number X of AB donors who come to a fixed Red Cross location per day This count has the Poisson distribution with parameter u being the mean number of AB donors per day a The donation center sees an average of 2 1 AB donors per day Find the Poisson probabilities for X 0 1 2 3 4 5 P X 0 P X 1

The null and alternative hypotheses for a population proportion as well as the sample results are given Use StatKey or other technology to generate a randomization distribution and calculate a p value StatKey tip Use Test for a Single Proportion and then Edit Data to enter the sample information Round the p value to three decimal places Hypotheses Ho p 0 5 vs Ha p 0 5 38 100 Sample data p H 0 38 with n 100

The null and alternative hypotheses for a test are given as well as some information about the actual sample and the statistic that is computed for each randomization sample Indicate whether the test is a left tail test a right tail test or a two tailed test 4 Ho p 0 vs Ha p 0 Sample r 0 20 n 40 Randomization statistic r Indicate where the randomization distribution will be centered i Indicate whether the test is a left tail test a right tail test or a two tailed test

Use the bootstrap distributions in Figure 1 to estimate the value of the sample statistic and standard error and then us information to give a 95 confidence interval In addition give notation for the parameter being estimated The bootstrap distribution in Figure 1 generated for a sample mean a Give the sample statistic for the parameter being estimated Round your answer to the nearest integer Sample statistic i 0 40 eTextbook and Media Hint Your answer is incorrect b Estimate the standard error Standard error i 0 05 c Give the 95 confidence interval The 95 confidence interval is i eTextbook and Media Hint X Your answer is incorrect 0 2 d Give notation for the parameter being estimated The correct notation is 16 19 22 25 28 31 34 Figure 1 Bootstrap distribution to i 0 6 Assistance Used

information to give a 95 confidence interval In addition give notation for the parameter being estimated The bootstrap distribution in Figure 1 generated for a sample proportion Sample statistic i eTextbook and Media a Give the sample statistic for the parameter being estimated Round your answer to one decimal place b Estimate the standard error Round your answer to one decimal place Standard error i eTextbook and Media c Give the 95 confidence interval Round your answers to one decimal place The 95 confidence interval is i Alle eTextbook and Media 0 5 0 6 0 7 0 8 0 9 Figure 1 Bootstrap distribution d Give notation for the parameter being estimated to i

Find the 5 number summary for the data shown 6 12 13 28 41 49 51 56 63 71 72 76 78 80 5 number summary 6 0 28 O 53 5 O 24 2 X 800 12 IQR 1 The 1 5 x IQR rule states that values between 32 X and 124 X are likely not outli

K The graph to the right shows the number of cities with certain average annual snowfall amounts in inches Identify the level of measurement of the data listed on the horizontal and vertical axes in the figure Identify the level of measurement of the data listed on the horizontal axis in the figure Choose the correct answer below O Ordinal 0000 O Nominal Interval Ratio Identify the level of measurement of the data listed on the vertical axis in the figure Choose the correct answer below O O point s possible Nominal Interval Ratio Ordinal Annual snowfall Submi ABCD Number of citi

Identify the sampling technique used In a recent telephone survey participants were asked to answer yes or no to the question Are you in favor of the death penalty Six thousand five hundred responded yes while 5700 responded no Only those who accepted a fifty cent charge for the call participated OA convenience OB cluster OC stratified OD random O E systematic

K ampling techniques used and discuss potential sources of bias if any Explain Assume the population of interest is the student body at a university Questioning students as they leave a student union building a researcher asks 340 students about their eating habits What type of sampling is used O A Systematic sampling is used because students are selected from a list with a fixed interval between students on the list OB Simple random sampling is used because students are chosen at random O C Cluster sampling is used because students are divided into groups groups are chosen at random and every student in one of those groups is sampled OD Stratified sampling is used because students are divided into groups and students are chosen at random from these groups OE Convenience sampling is used because students are chosen due to convenience of location What potential sources of bias are present if any Select all that apply DOO A Because of the personal nature of the question students may not answer honestly B University students may not be representative of all people in their age group C The sample only consists of members of the population that are easy to get These members may not be representative of the population D There are no potential sources of bias

The jersey numbers for players on a basketball team are listed below 13 31 4 29 Identify the level of measurement of the data set Explain your reasoning 2 9 18 42 72 24 21 33 12 16 10 19 What is the data set s level of measurement Explain your reasoning OA Nominal The data are categorized using numbers but no mathematical computations can be made OB Ordinal The data can be arranged in order or ranked but differences between data entries are not meaningful OC Ratio The data can be ordered and differences between data entries are meaningful and the zero entry is an inherent zero OD Interval The data can be ordered and differences between data entries are meaningful but the zero entry is not an inherent zero 15 14 7 91

A study of 803 senior citizens shows that participants who exercise regularly exhibit less of a decline in the cognitive ability than those who barely exercise at all From this study a researcher infers that your cognitive ability increases the more you exercise What is wrong with this type of reasoning The inference imply that exercise does correctly may incorrectly H a person s cognitive ability The study shows in cognitive ability

K Is an inherent zero Describe three examples of data sets that have inherent zeros and three that do not Choose the correct answer below OA An inherent zero is a value that the variable can take OB An inherent zero is a zero that implies none OC An inherent zero is a zero that occurs in the data set naturally Select three examples of data sets that have inherent zeros below A Average monthly precipitation in inches B Average IQ score of a high school class C Temperature in degrees Fahrenheit D A student s level of happiness measured from 0 to 10 E Average age of college students in years F Maximum wind speed during a hurricane Select three examples of data sets that do not have inherent zeros below A Temperature in degrees Fahrenheit B Average IQ score of a high school class C A student s level of happiness measured from 0 to 10 D Average age of college students in years E Average monthly precipitation in inches F Maximum wind speed during a hurricane

Determine whether the underlined numerical value is a parameter or a statistic Explain your reasoning A survey of 42 out of hundreds in a dining hall showed that 40 5 enjoyed their meal Choose the correct answer below OA Statistic because the data set of 42 people in a dining hall is a sample B Parameter because the data set of 42 people in a dining hall is a sample OC Statistic because the data set of 42 people in a dining hall is a population OD Parameter because the data set of all people in the dining hall is a sample OE Statistic because the data set of all people in the dining hall is a population OF Parameter because the data set of all people in the dining hall is a population G Statistic because the data set of all people in the dining hall is a sample OH Parameter because the data set of 42 people in a dining hall is a population

Identify the data set s level of ages of students in a statistic class OA ratio OB ordinal O C nominal OD interval measurement

A modified roulette wheel has 44 slots One slot is 0 another is 00 and the others are numbered 1 through 42 respectively You are placing a bet that the outcome is an odd number In roulette 0 and 00 are neither odd nor even Type an integer or a simplified fraction b What are the actual odds against winning The actual odds against winning are 23 21 c When you bet that the outcome is an odd number the payoff odds are 1 1 How much profit do you make if you bet 19 and win If you win the payoff is 19 d How much profit should you make on the 19 bet if you could somehow convince the casino to change its payoff odds so that they are the same as the actual odds against winning s Round to the nearest cent as needed

Choose the correct answer below ets that have inherent zeros and three that do not O A An inherent zero is a zero that occurs in the data set naturally B An inherent zero is a zero that implies none OC An inherent zero is a value that the variable can take Select three examples of data sets that have inherent zeros below A Maximum wind speed during a hurricane B A student s level of happiness measured from 0 to 10 C Average age of college students in years D Temperature in degrees Fahrenheit E Average IQ score of a high school class F Average monthly precipitation in inches Select three examples of data sets that do not have inherent zeros below A Maximum wind speed during a hurricane B Average monthly precipitation in inches C Average age of college students in years D Average IQ score of a high school class E Temperature in degrees Fahrenheit F A student s level of happiness measured from 0 to 10

Identify the data set s level of measurement temperatures of 20 selected refrigerators O A interval OB nominal OC ratio OD ordinal

a Marital status c Pain level scale of 0 to 10 intake form Identify the level of measurement of the data a What is the level of measurement for Marital status O Nominal O Ratio O Interval O Ordinal b What is the level of measurement for Year of birth O Ordinal O Nominal O Interval O Ratio c What is the level of measurement for Pain level scale of 0 to 10 O Ratio O Ordinal O Interval O Nominal d What is the level of measurement for Height O Nominal O Interval O Ordinal UP b Year of birth d Height

Identify the sampling technique used A researcher for an airline interviews all of the passengers on five randomly selected flights A random B cluster C stratified D systematic O E convenience