Statistics Questions

Surveys tend to suffer from low response rates Based on past experience a researcher determines that the typical response rate for an e mail survey is 40 She wishes to obtain a sample of 500 respondents so she e mails the survey to 2500 randomly selected e mail addresses Assuming the response rate for her survey is 40 will the respondents form an unbiased sample Explain Is the sample unbiased OA Yes The sample was a randomly selected group of e mail addresses which does not introduce bias OB Yes The number of respondents will be approximately 1000 that is two times greater than the needed size of the sample O C No The survey was not given to the entire population O D No The survey still suffers from undercoverage sampling bias nonresponse bias and potentially response bias

The manager of a shopping mall wishes to expand the number of shops available in the food court He has a market researcher survey the first 120 customers who come into the food court during weekend evenings to determine what types of food the shoppers would like to see added to the food court Complete parts a and b below a The survey has bias Determine whether the flaw is due to the sampling method or the survey itself For biased surveys identify the cause of the error What is the cause of the bias OA Nonresponse B Sampling bias OC Response bias

What does it mean when a part of the population is under represented Choose the correct answer below OA A part of the population is under represented when their answers on a survey tend not to reflect their true feelings OB A part of the population is under represented when individuals selected to be in the sample who do not respo to the survey have different opinions from those who do OC A part of the population is under represented when it is proportionally smaller in a sample than in its populatic OD A part of the population is under represented when it is proportionally smaller in its population than in a samp

What is a closed question What is an open question Discuss the advantages and disadvantages of each type of question What is a closed question What is an open question OA A closed question always has yes or no answers whereas an open question is a free response question OB A closed question has many correct answers whereas an open question has only one correct answer OC A closed question has fixed choices for answers whereas an open question is a free response question OD A closed question is a free response question whereas an open question has fixed choices for answers

ND 003 AZ 004 WA 007 NV 11 UT 27 CA 41 MT 142 CA 150 OR 58 UT 59 AZ 60 WA 62 UT 73 CO 74 CO 88 WA 94 NV 109 HI 20 OR 55 OR 62 UT 165 WA 657 CA 58 MT 54 AZ 17 UT 29 CA 85 CO 51 AZ 56 08 State ProductID Bulk Quanity for Discount Product Name 100 QuickStove 100 QuickStove 100 QuickStove 100 QuickStove 100 QuickStove 102 Replacement Fuel Cells 104 Quick Stove Can 104 Quick Stove Can 104 Quick Stove Can 102 Replacement Fuel Cells 104 Quick Stove Can 102 Replacement Fuel Cells 104 Quick Stove Can 102 Replacement Fuel Cells 102 Replacement Fuel Cells 102 Replacement Fuel Cells 102 Replacement Fuel Cells 102 Replacement Fuel Cells 106 Stove In A Can 106 Stove In A Can 106 Stove In A Can 106 Stove In A Can 106 Stove In A Can 106 Stove In A Can 108 QuickStove Fuel Disk 107 SIAC Fuel Cell 106 Stove In A Can 107 SIAC Fuel Cell 107 SIAC Fuel Cell Unit Price 17 55 17 55 17 55 17 55 17 55 4 00 34 99 34 99 34 99 4 00 34 99 4 00 34 99 4 00 4 00 4 00 4 00 4 00 34 99 34 99 34 99 34 99 34 99 34 99 1 66 5 00 34 99 5 00 5 00 10 Quantity Multiple Items TRUE TRUE TRUE TRUE FALSE FALSE TRUE TRUE TRUE TRUE TRUE TRUE FALSE TRUE FALSE 4 S 7 12 1 1 2 8 8 4 2 16 1 5 1 2 2 10 1 3 1 3 1 12 24 2 2 10 4 TRUE TRUE TRUE FALSE TRUE FALSE TRUE FALSE TRUE TRUE TRUE TRUE TRUE TRUE Multi Month UT OR Bulk Order FALSE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE TRUE TRUE FALSE FALSE TRUE FALSE Single Month CO NV Multi Month IF C8 Single Month Send Promo M20 complete the Bulk Order column on the table Be sure to appropriately use relative and absolute cell references E 7 1 3 Calculate Multi Month in cell 18 Use a Boolean formula that returns TRUE if the State cell C8 matches one of the months in the Multi Month column range 14 15 Use an OR function Copy your function down to complete the Multi Month column 5 1 4 Calculate Single Month in 1 5 Calculate Send Promo in

following data represent the number of games played in each series of an annual to 1923 to 2019 Complete parts a through d below games played 4 5 6 7 Frequency 20 22 22 32 M555 The series if played many times would be expected to last about 1 14 game s average Ompute the standard deviation of the random variable X game s d to one decimal place as needed

The unemployment rate in a city is 15 If 8 people from the city are sampled at random find the probability that at least 2 of them are unemployed Carry your intermediate computations to at least four decimal places and round your answer to two decimal places If necessary consult a list of formulas

e probability distribution to the right the random variable X represents the ber of hits a baseball player obtained in a game over the course of a son Complete parts a through f below offet 012345 Number of Hits oftl distribution 0 1 2 3 4 5 Number of Hits scribe the shape of the distribution and is 4 0 1 2 3 4 5 Number of Hits X012345 P X 0 168 0 335 0 284 0 148 0 038 0 024 0 1 2 3 4 Number of Hit

A spinner with 5 equally sized slices has 2 yellow slices 2 red slices and 1 blue slice Leila spun the dial 1000 times and got the following results Outcome Number of Spins Answer the following Round your answers to the nearest thousandths Yellow 414 Red 366 a From Leila s results compute the experimental probability of landing on red Blue 220 b Assuming that the spinner is fair compute the theoretical probability of landing on red c Assuming that the spinner is fair choose the statement below that is true O The larger the number of spins the greater the likelihood that the experimental probability will be close to the theoretical probability O The smaller the number of spins the greater the likelihood that the experimental probability will be close to the theoretical probability O The experimental probability will never be very close to the theoretical probability no matter the number of spins X S 4

marketing company runs a web campaign that includes running an ad on the common platforms There are an average of 3 3 ad clicks per hour the Poisson distribution to find the probability that there are exactly 4 ad clicks in a given hour not round intermediate computations and round your answer to three decimal places necessary consult a list of formulas X S 4

the time Suppose 13 flights are randomly selected and the number of on time flights is a Explain why this is a binomial experiment b Determine the values of n and p c Find and interpret the probability that exactly 9 flights are on time d Find and interpret the probability that fewer than 9 flights are on time e Find and interpret the probability that at least 9 flights are on time f Find and interpret the probability that between 7 and 9 flights inclusive are on time b Using the binomial distribution determine the values of n and p Type an integer or a decimal Do not round Type an integer or a decimal Do not round n p c Using the binomial distribution the probability that exactly 9 flights are on time is n

Grand Sun Buffet is a large restaurant chain After paying for a meal at Grand Sun Buffet customers are asked to rate the quality of the food as a 1 2 3 4 or 5 where a rating of 1 means not good and 5 means excellent The customers ratings have a population mean of 4 33 with a standard deviation of G 1 39 Suppose that we will take a random sample of n 6 customers ratings Let x represent the sample mean of the 6 customers ratings Consider the sampling distribution of the sample mean x Complete the following Do not round any intermediate computations Write your answers with two decimal places rounding if needed a Find the mean of the sampling distribution of the sample mean X S b Find o the standard deviation of the sampling distribution of the sample mean Mex 6

termine whether the random variable is discrete or continuous In each case alues of the random variable The number of customers arriving at a bank between noon and 1 00 PM The time it takes for a light bulb to burn out OD The random variable is discrete The possible values are x 20 b is the time it takes for a light bulb to burn out discrete or continuous OA The random variable is continuous The possible values are t 1 2 3 OB The random variable is discrete The possible values are t 0 OC The random variable is continuous The possible values are 10 OD The random variable is discrete The possible values are t 1 2 3

A binomial experiment with probability of success p 0 5 and n 7 trials is conducted What is the probability that the experiment results in exactly 1 success Do not round your intermediate computations and round your answer to three decimal places If necessary consult a list of formulas

e following data represent the number of games played in each series of an annua m 1923 to 2019 Complete parts a through d below games played Frequency 4 5 6 7 20 22 22 32 5 6 0 4 5 Compute and interpret the mean of the random variable X game s 7 4

from 1923 to 2019 Complete parts a through d below 7 Q x games played Frequency OA AP x 0 5 4 5 6 7 4 5 6 20 22 22 32 B AP x 0 5 4 5 6 7 O C AP X 0 5 4 5 6 7 O D AP x 0 5 10

A fair die is rolled 4 times What is the probability that a 6 is obtained on at least one of the rolls Round your answer to three decimal places If necessary consult a list of formulas 0 X S h

A binomial pro probability of x successes in the n independent trials of the experiment n 9 p 0 4 x 3 The probability of x 3 successes is Round to four decimal places as neede

robability distribution to the of hits a baseball player obtained in a game over the course of a Complete parts a through f below 012345 an integer or a decimal Do not round at is the probability that in a randomly selected game the player got more than

probabilit right number of hits a baseball player obtained in a game over the course of a season Complete parts a through f below O A 0 4 0 3 0 2 0 1 O B 0 4 0 31 0 2 0 1 0 O C Probability 0 4 0 3 0 2 0 1 0 O D Probability 0 4 321 0 3 0 2 0 1 0 2 3 4 5 0 168 0 335 0 284 0 148 0 038 0 024

a If 400 murders are randomly selected how many would we expect to be committe a firearm b Would it be unusual to observe 290 murders by firearm in a random sample of 400 Why b Choose the correct answer below OA Yes because 290 is between 20 and 20 OB Yes because 290 is greater than u 20 OC No because 290 is between 20 and 20 OD No because 290 is less than 20 OE No because 290 is greater than 20

Today the waves are crashing onto the beach every 5 4 seconds The times from when a person arrives at the shoreline until a crashing wave is observed follows a Uniform distribution from 0 to 5 4 seconds Round to 4 decimal places where possible a The mean of this distribution is 2 7 08 b The standard deviation is 1 5588 OF c The probability that wave will crash onto the beach exactly 0 9 seconds after the person arrives is P x 0 9 0 0000 d The probability that the wave will crash onto the beach between 1 8 and 2 7 seconds after the person arrives is P 1 8 x 2 7 e The probability that it will take longer than 1 98 seconds for the wave to crash onto the beach after the person arrives is P x 1 98 f Find the maximum for the lower quartile seconds

The age of children in kindergarten on the first day of school is uniformly distributed between 4 97 and 5 77 years old A first time kindergarten child is selected at random Round answers to 4 decimal places if possible a The mean of this distribution is 5 37 b The standard deviation is c The probability that the the child will be older than 5 years old d The probability that the child will be between 5 07 and 5 27 years old is e If such a child is at the 88th percentile how old is that child years old

Bus wait times are uniformly distributed between 6 minutes and 22 minutes The unshaded rectangle below with area 1 depicts this The shaded rectangle depicts the probability that a randomly selected bus wait time will be between 9 and 16 minutes Give answers to the following questions in fraction form 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 The base of the shaded rectangle is The height of the rectangle is

Keegan is investigating how long his phone s battery lasts in hours for various brightness levels on a scale of 0 100 His data is displayed in the table and graph below Brightness Level x Hours y 10 9 8 7 6 Hours S 3 2 1 10 20 30 18 19 5 5 6 3 31 37 5 7 7 40 50 60 Brightness Level What is the residual for the point 31 7 7 Round to 4 decimal places hours 41 4 4 61 79 84 3 6 2 2 4 70 80 90 100 H

Suppose that the number of drivers who travel between a particular origin and destination during a designated time period has a Poisson distribution with parameter 20 suggested in the article Dynamic Ride Sharing Theory and Practice Round your answer to three decimal places a What is the probability that the number of drivers will be at most 16 b What is the probability that the number of drivers will exceed 26 c What is the probability that the number of drivers will be between 16 and 26 inclusive What is the probability that the number of drivers will be strictly between 16 and 26 d What is the probability that the number of drivers will be within 2 standard deviations of the mean value

Interpreting a Linear Equation At 12 00 P M the volume of water in a tank started changing steadily over time The volume V measured in gallons t minutes after the water volume started to change is given by the equation V 40800 20 4t gallons and that the volume The equation tells us that the volume of water in the tank was initially is Select an answer by Select an answer

Terry is skiing down a steep hill Terry s elevation E in feet after t seconds is given by E 4100 50 t Where t can be any number from 0 to 10 The slope 50 is Terry s change in elevation for each second and the y intercept 4100 is Terry s starting elevation The slope 50 is how steep the mountain is and the y intercept 4100 is the height of the mountain The slope 50 is Terry s speed as he skis down the mountain and the y intercept 4100 is how far Terry travels in 10 seconds The slope 50 is how steep the mountain is and the y intercept 4100 is Terry s starting elevation The slope 4100 is Terry s change in elevation for each second and the y intercept 50 is Terry s starting elevation

ccording to flightstats com American Airlines flights from Dallas to Chicago are on time me time Suppose 24 flights are randomly selected and the number of on time flights is a Explain why this is a binomial experiment Determine the values of n and p Find and interpret the probability that exactly 16 flights are on time d Find and interpret the probability that fewer than 16 flights are on time e Find and interpret the probability that at least 16 flights are on time Find and interpret the probability that between 14 and 16 flights inclusive are on tim

What Cl formula would you use for a sample size of 10 subjects O Interval Ratio formula using the Z score O Interval Ratio formula using the T score Proportions formula using the Z score

A pharmaceutical company wants to conduct a survey 20 individuals who have high cholesterol The company has obtained a list from primary care physicians throughout the country of 3600 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 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 B 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 C Alphabetize the list of 3600 individuals by last name and select one of the first 180 individuals at random Starting from the selected individual read down the list and select every 180th individual D 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

ine whether the random variable is discrete or continuous In each case state of the random variable number of customers arriving at a bank between noon and 1 00 P M distance a baseball travels in the air after being hit ne number of customers arriving at a bank between noon and 1 00 P M discre inuous The random variable is continuous The possible values are x 20 The random variable is discrete The possible values are x 20 The random variable is continuous The possible values are x 0 1 2 The random variable is discrete The possible values are x 0 1 2

oor Complete parts a through c For 250 randomly selected adults compute the mean and standard deviation of the able X the number of adults who believe that the overall state of moral values is po e mean of X is Round to the nearest whole number as needed

4 Type an integer or a decimal AXXB 45 6

old female for 280 According to the National Vital Statistics Report 58 21 the ity that the female survives the year is 0 999544 Compute and interpret the exp this policy to the insurance company pected value is to the nearest cent as needed

strong the investment will result in a profit of 30 000 If the economy e pace the investment will result in a profit of 20 000 However if the ssion the investment will result in a loss of 30 000 You contact an e there is a 30 probability the economy will remain strong a 60 prob will grow at a moderate pace and a 10 probability the economy wil n What is the expected profit from this investment ected profit is Type an integer or a decimal

graph of the discrete bability to the right resents the number of births by a mother 46 51 years old who had a birth in 2015 mplete parts a ough d below Probability 0 30 0 25 0 20 0 15 0 10 0 05 0 00 0 0 235 0 275 0165 0 113 0 099 0024 0 033 3 4 5 6 Number of Live Births 7 0 056 8 113 Type an integer or a decimal What is the probability that a randomly selected 46 to 51 year old mother who had 2015 has had her fourth or fifth live birth in that year Type an integer or a decimal

Choose the correct answer below OA A random variable is a numerical measure having either a finite or countal of values of the outcome of a probability experiment OB A random variable is a numerical measure of the outcome of a probability OC A random variable is a numerical measure having values that can be plott an uninterrupted fashion of the outcome of a probability experiment

www A The experiment is performed a fixed number of times B Each trial depends on the previous trial C The experiment is performed until a desired number of successes is rea D There are three mutually exclusive outcomes arriving on time arriving arriving late E The probability of success is different for each trial of the experiment F The trials are independent G There are two mutually exclusive outcomes success or failure H The probability of success is the same for each trial of the experiment

Choose the correct answer below O A As n decreases the binomial distribution becomes more bell shaped OB As n increases the binomial distribution becomes skewed right OC As n decreases the binomial distribution becomes skewed left OD As n increases the binomial distribution becomes more bell shaped OE The value of n does not affect the shape of the binomial probability histogram

t of a 6th to 8th grade student is involved in Complete parts a through f below to 0 376 t 0 0 092 X P x 2 3 4 D 0 191 0 098 0 243 C rify that this is a discrete probability distribution a discrete probability distribution because the sum of the probabilities is Dility is and

etermine whether the distribution is a discrete probability ibution 0 1 2 3 4 0 21 0 35 0 11 0 14 0 19 the distribution a discrete probability distribution OA No because the sum of the probabilities is not equal to 1 OB Yes because the sum of the probabilities is equal to 1 and each probability is between and 1 inclusive OC Yes because the sum of the probabilities is equal to 1 OD Yes because each probability is between 0 and 1 inclusive

Choose the correct answer below Select all that apply A 0 P x 1 B P x 0 C 0 P x 1 D P x 1

raph of the discrete bility to the right sents the number of ths by a mother 46 years old who had a rth in 2015 lete parts a gh d below Probability 0 30 0 25 0 20 0 15 0 10 0 05 0 00 0 0 235 0 275 0 165 0 113 0 099 0 024 0 033 3 4 5 6 7 Number of Live Births 0 056 8 hat is the probability that a randomly selected 46 to 51 year old mother who hac 5 has had her fourth live birth in that year ype an integer or a decimal

Suppose a marketing firm wants to gather information about a new product The firm divided a city into blocks as illustrated Note the numbers shown represent house address numbers Which of the following represents a possible cluster sample of the homes in the city 1369 1371 1373 1375 7480 7484 1370 1372 1374 1376 7483 7487 7491 7495 1414 1416 1418 1420 8017 8021 8025 8029 1415 1417 1419 1421 Choose the correct answer below 8020 8024 8028 8032 1544 1546 1548 1550 9052 9056 9060 9064 OA 7480 7483 7484 7487 7488 7491 7492 7495 B 1369 1374 1547 1685 1421 6589 9056 8025 O C 1417 1687 1369 9060 1421 7487 1547 1544 O D 6589 1415 1687 7492 9064 8021 1369 1546 1545 1547 CLEED 1549 1551 9055 9059 9063 9067 1683 1685 1687 1689 6574 6578 6582 6586 1684 1686 7488 7492 This is a reading assessment question Be certain of your answer because you only get one attempt on this question 1688 1690 6577 6581 6585 6589

The human resource department at a certain company wants to conduct a survey regarding worker benefits The department has an alphabetical list of all 5154 employees at the company and wants to conduct a systematic sample of size 50 a What is k k 103 b Determine the individuals who will be administered the survey Randomly select a number from 1 to k Suppose that we randomly select 7 Starting with the first individual selected the individuals in the survey will be 0

A club wants to sponsor a panel discussion on an upcoming election The club wants to have four of its members lead the panel discussion To be fair however the panel should consist of two members of each party Below is a list of members in each party Obtain a stratified sample of two people from party 1 and two from party 2 Bolden Carter Haydra Lukens Party 1 Nolan Pawlak Tate Wright Cooper Engler Keating May Party 2 Ochs Rice Thomas Weber Which of the following is a possible list of club members to lead the panel discussion O A Bolden Carter Pawlak Nolan B Bolden Carter Weber May OC Bolden Carter Pawlak Weber OD Weber May Rice Thomas OE Weber May Rice Bolden

For a poll of voters regarding a referendum calling for a national railways development program design a sampling method to obtain the inviduals in the sample Be sure to support your choice Which sampling method would most likely be used in a poll of voters regarding a referendum calling for a national railways development program OA Use convenience sampling A large number of voters is needed to accurately reflect the nation s voters so a quick way to collect information is needed OB Use simple random sampling Simple random sampling is always the best sampling method to choose regardless of the survey conducted OC Use stratified random sampling Since this is a national issue different geographical locations are likely to have similar views OD Use cluster sampling Each geographical region can be treated as a mini population because voting results are independent of region OE Use systematic random sampling By varying the k value a sampling of the whole nation can be selected to achieve the needed accuracy

A pharmaceutical company wants to conduct a survey of 50 individuals who have high cholesterol The company has obtained a list from primary care physicians throughout the country of 11 500 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 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 50 C 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 50 individuals with high cholesterol D Alphabetize the list of 11 500 individuals by last name and select one of the first 230 individuals at random Starting from the selected individual read down the list and select every 230th individual

6 Suppose the length of time in hours between emergency arrivals at a certain hospital is modeled as an exponential distribution with 4 a What is the probability that more than 5 hours pass without an emergency arrival b Find P 1 X 3 c Find a approximately such that P X a 0 19691168