Statistics Questions

Which of the following data sets or plots could have a regression line with a negative slope Select all that apply Select all that apply The number of tons of trash in a landfill as a function of the number of years since the landfill was built The number of loads of trash a dump truck hauls per month as a function of the number of years since the dump truck was built The number of tons of trash produced in a city as a function of population growth The number of minutes you will wait to drop off your trash at a landfill as a function of the number of dump trucks at the landfill

The least squares regression line for the cost of a diamond necklace from a department store y in dollars in the year x years since 2000 is given by y 1823 314x Interpret the y intercept of the least squares regression line Select the correct answer below The predicted cost of a diamond necklace from the department store is expected to increase 314 per year after the year 2000 O The predicted cost of a diamond necklace from the department store in the year 2000 is 1823 O The predicted cost of a diamond necklace from the department store in the year 2000 is 314 The y intercept should not be interpreted

A scientific study on lift strength gives the following data table Lift strength Tons 46 47 51 55 56 Time to move load seconds 159 166 123 128 117 Using technology it was determined that the total sum of squares SST was 1989 2 the sum of squares regressio SSR was 1598 1 and the sum of squares due to error SSE was 391 10 Calculate R2 and determine its mear Round your answer to four decimal places

Fishing Lines 4575 2 12 Fish caught 13 25 29 26 Using technology it was determined that the total sum of squares SST was 203 20 and the sum of squares due to SSE was 41 62 Calculate R and determine its meaning Round your answer to four decimal places Select the correct answer below 0 7952 Therefore 79 52 of the variation in the observed y values can be explained by the estimated regression equation 0 7952 Therefore 0 7952 of the variation in the observed y values can be explained by the estimated regression equation 0 2049 Therefore 20 49 of the variation in the observed y values can be explained by the estimated regression equation 0 2049 Therefore 0 2049 of the variation in the observed values can be explained by the estimated regressi n equation TERRENCY MORE INSTRUCTION S

exercise 50 53 56 60 64 35 44 49 65 69 Using technology it was determined that the total sum of squares SST was 819 2 the sum of squares regression SSR was 794 19 and the sum of squares due to error SSE was 25 013 Calculate R and determine its meaning Round your answer to four decimal places Select the correct answer below R 0 0305 Therefore 3 05 of the variation in the observed y values can be explained by the estimated regression equation R 1 0315 Therefore 10 315 of the variation in the observed y values can be explained by the estimated regression equation R 0 0315 Therefore 3 15 of the variation in the observed y values can be explained by the estimated regression equation R 0 9695 O Therefore 96 95 of the variation in the observed y values can be explained by the estimated regression equation E

fertilizer distance 15 88 15 101 18 116 20 93 21 122 Using technology it was determined that the total sum of squares SST was 854 the sum of squares regression SSR was 257 18 and the sum of squares due to error SSE was 596 82 Calculate R and determine its meaning Round your answer to four decimal places Select the correct answer below R 0 6989 Therefore 69 89 of the variation in the observed y values can be explained by the estimated regression equation R AN 0 3011 Therefore 30 11 of the variation in the observed y values can be explained by the estimated regression equation 3 3200 Therefore 3 32 of the variation in observed y values can be explained by the estimated regression equation R 2 3200 Therefore 2 32 of the variation in the observed y values can be explained by the estimated regression equation C

A news reporter wants to assess the top 30 college quarterbacks The reporter recorded the number of plays and the number of passes a quarterback completed in one season This sample data is provided below Use Excel to calculate the correlation coefficient between the two data sets Round your answer to two decimal places Plays 519 678 373 319 496 430 542 357 642 Passes 104 3 109 4 50 7 43 7 83 6 47 4 49 4 74 7 99 6

orge is an economist trying to understand whether there is a strong link between CEO compensation and corporate evenue He gathered data including the CEO compensation for 30 randomly selected corporations for a particular year as vell as the corporate revenue of those corporations for the same year The data Jorge gathered are provided in the accompanying data table Use Excel to calculate the correlation coefficient r between the two data sets Round your answer o two decimal places CEO Compensation 14215830 14499807 15268679 14476928 15083546 15237297 13881835 13771160 14269205 Help Corporate Revenue million 20101 28266 18524 28738 Copy to clipboard 52884 117162 23704 33749 62478 Download CSV

A researcher is interested in whether the variation in the size of human beings is proportional throughout each part of the human To partly answer this question they looked at the correlation between the foot length in millimeters and height in centimeters of 30 randomly selected adult males The data is provided below Use Excel to calculate the correlation coefficient r between the two data sets Round your answer to two decimal places Foot length mm 244 9 248 5 248 1 252 3 251 6 256 5 240 3 252 7 259 7 Height cm 159 2 164 8 173 7 171 7 164 6 171 4 179 7 183 1 183 2

The table below represents the number of young people in a certain city enrolled in the academic support and enrichment program of youth services Here I represents the number of months from January 2011 and y represents the number of young people enrolled Use Excel to find the best fit linear regression equation Round the slope and intercept to two decimal places X 0 1 2 3 4 5 6 y 3199 3282 3432 3245 3076 3485 1524

A recent graduate moving to a new job collected a sample of the monthly rent in dollars and the size in square feet of 3 bedroom apartments in one area of a city Use Excel to find the best fit linear regression equation where size of the apartment is the explanatory variable Round the slope and intercept to two decimal places Size 961 949 924 920 902 893 888 886 Rent 909 1048 841 704 1131 867 2532 800

alues corresponds to the points ntent attribution percent of repaired machines is the y coordinate So the table of 40 20 26 40 20 50 15 65 10 70 FEEDBACK Question Using the linear relationship graphed above estimate the percent of repaired machines if 35 of the machines have defects

Using the linear relationship graphed above estimate the percent of repaired machines if 35 of the machines have defects Provide your answer below

Problem 3 Let X X2 X7 denote idenpendent random samples from a population having 10 mean and variance o Consider the following estimators of 1 Is either estimator unbiased Which estimator is better In what sense is better Hint Can you compare the variance of both estimators X X X7 7 2X X6 X 2

4 3 2 1 0 0 4 4 8 8 12 12 16 16 20 20 24 24 28 28 32 36 40 32 36 40 44 44 48 52 56 b We expect the median value to fall between 12 48 52 56 60 Sugar by weight 1 point The histogram displays the sugar content as a percent of weight of 49 brands of breakfast cereals a How many cereals have between 4 and 8 percent sugar by weight 14 60 64 and 16

0 4 4 8 8 12 12 16 16 20 20 24 24 28 28 32 32 36 36 40 t 40 44 44 48 48 52 52 56 b We expect the median value to fall between 12 56 60 Sugar by weight 1 point The histogram displays the sugar content as a percent of weight of 49 brands of breakfast cereals a How many cereals have between 4 and 8 percent sugar by weight 14 ond 60 64

A parabola best represents the data because there is not a constant rate of change b Use the regression feature of your calculator to find the model that best fits the data The model is h c Use the model in part b to predict when the sponge will hit the ground Round your answer to the nearest hundredth about seconds d Identify and interpret the domain and range in this situation The domain is The range is t h The domain represents the time the sponge was in the air and

The owner of a large textile company explored the relationship between the percent of defects and the percent of R repaired machines at various textile facilities throughout the region The owner collects information from 5 of their facilities shown in the table below Use the graph below to plot the points and develop a linear relationship between the percent of defects and the percent of repaired machines Provide your answer below of repaired machines 100 90 80 70 60 30 20 Facility Number of Defects of Repaired Machines 20 40 50 65 70 Facility 3 38 65 Facility 2 18 48 10 Facility 1 9 34 8 3 4 5 40 26 20 15 10 Facility 5 76 68 Facility 4 180 47

2 A card is drawn at random from a standard deck of cards What is the probability that the card is a face card or a diamond card given that it is red ashamed overjoyed bewildered shocked A 8 13 B 1 2 C 17 26 D 6 13 E 4 13 nervous Gina Wilson All Things Algebra LLC 2018

A 1 4 B 1 3 C 5 24 D 3 8 E 7 24 7 14 15 8 21 222 A 9 10 16 17 23 24 28 29 30 31 11 12 18 19 25 26 Sara chose a date from the calendar shown above What is the probability that the date she chose is a prime number given that the date is after the 7th of the month 13 20 27 Mr Wright Ms Gilmore Mrs Silvertooth Mrs Van Duyn Mr Bowen Gina Wilson All Things Algebra LLC 2018

How much time did a person spend at the library over a month for them to spend 40 hours reading a book Round your final answer to the nearest whole number Provide your answer below hours

Upon landing airplane passengers were asked if they checked their bags and if this was their final destination Results are shown in the table below If a passenger is chosen at random find P checked bags final destination 10 5 Yes Bags No Checked A 72 4 B 68 1 C 65 3 D 64 7 E 63 2 Final Destination Yes 64 30 No 90 16 trolley bounce house haunted house space shuttle planetarium Gina Wilson All Things Algebra LLCJ 2018

Members at a gym were asked if they track their fitness and if they attend classes offered at the gym The results are given in the table below as relative joint and marginal frequencies If a person from the gym is chosen at random find the probability that they do not attend classes given they track their fitness Track Fitness Attend Classes A 31 7 B 32 5 C 34 8 D 36 1 07 Yes No Total Yes 0 384 0 24 0 624 No 0 256 0 12 0 376 Total 0 64 0 36 1 doing crunches playing with playdoh arm wrestling writing rap songs na hanios

A school survey reported that 80 of the students have cell phones 45 have part time jobs and 30 have both a cell phone and a part time job If a student is chosen at random what is the probability that the student has a part time job given that they have a cell phone Graduation Day Open House Night A 25 B 32 5 C 35 D 37 5 E 40 Halloween Valentine s Day April Fools Day Gina Wilson All Things Algebra LLC 2018

A 83 2 B 85 8 C 89 3 D 90 4 E 92 6 Boy Girl MI Pass 46 50 The table below shows the results of a final exam taken by Mr Harvey s math students If one of his students is chosen at random find P pass girl 6006 2 Fail 18 6 G MA 35 football helmets tu tus pink leggings monkey costumes hair nets Ging Wilson All Things Algebra LLC 2018 4000

A restaurant sells chocolate and vanilla milkshakes in three sizes Milkshake orders for a certain day are given in the table below as relative joint and marginal frequencies Based on this data if a milkshake order is placed find P vanilla medium or large Cup Size Flavor Chocolate Vanilla Total A 39 5 B 41 2 C 43 7 D 44 9 E 46 4 Small 0 10 0 05 0 15 Medium 0 30 0 225 0 525 Large 0 20 0 125 0 325 Total 0 60 0 40 1 were live on Instagram lost a bet won a radio contest were on vacation wanted to get a laugh

4 Of the 100 employees at a company 75 are married and 57 have at least one child Thirty three of the employees married do not have any children If an employee is chosen at random find P has at least one child married A 14 25 B 7 15 C 2 5 D 11 25 E 19 30 Mr Van Duyn Mr Kissick Mrs Van Duyn Mr Kronstedt Ms McClanahan Gina Wilson All Things Algebra LLCJ 2018

3 Of the 60 students in orchestra 24 are in chorus and 15 are in photography Four of the students are in chorus and photography If one student is chosen at random what is the probability that this student is in chorus given that they are not in photography A 9 20 B 2 5 C 4 9 D 5 12 E 1 3 playing basketball mini golfing doing leg extensions snowboarding driving bumper cars Gina Wilson All Things Algebra LLC 2018

Ron s realtor sent him listings for a new house Of the listings sent 60 are two story homes 24 have a pool and 15 are two story homes with a pool If Ron chooses a house at random find P pool not two story A 18 2 B 20 8 C 21 6 D 22 5 E 24 5 fishing pier gas station race track hair salon hospital Gina Wilson All Things Algebra LLC 2018

A librarian finds that the number of hours spent reading a book over a month R is dependent on the number of hours a person spends at the library over a month z and can be modeled by the function R z 1 5x 26 Draw the graph of the reading function by plotting its R intercept and another point Provide your answer below Hours Reading 24 50 10 10 15 25 2640 30 35 20

Opening Activity day 15 The two way table shows the results of a survey of what people were wearing on a fall day Match each outfit combination with its probability to the nearest tenth of a percent A belt B no sweater C sweater and no belt 2 helt and no sweater 1 6 7 2 17 5 3 29 2 A Place an

How many hours does a student need to study during the week for the final to only have 10 problems marked incorrect If necessary round your final answer to the nearest whole number Provide your answer below hours

The Venn diagram shows the frequency of events A and B 625 A Part A What is P A and B Part B What is P A or B 20 255 B 135

The number of questions marked incorrect on a final y is dependent on the number of hours the student studies during the week I and can be modeled by the function g z 40 2 5 Draw the graph of the function by plotting its y intercept and another point Provide your answer below Number of Incorrect Problems 60 50 40 30 20 10 0 16 2640 F

How much water should be consumed every two hours for a person to run 16 miles Round your final answer to the nearest whole number Provide your answer below ounces

A runner finds that the distance they run in miles D is dependent on the ounces of water consumed every two hours Z and can be modeled by the function D z 1 5z Draw the graph of the distance function by plotting its D intercept and another point Provide your answer below Distance in miles 0 0 16 5 30 SALKKA Calanner in SINTACT

The scatter plot below shows data relating competitive chess players ratings and their IQ Which of the following patterns does the scatter plot show Chess ratings 2000 1800 1600 1400 1200 1000 800 600 75 80 85 90 95 100 105 110 115 120 6

Scatter plot below shows data relating to income and the number of children a family has Which of the following patterns does the scatte 200 Plot Show Spure shout 150 100 Income 50 1 DA D 6 O 1 2 3 4 5 6 7 Number of children Positive linear pattern Positive linear pattern with deviations Negative linear pattern

Enter the relative frequencies in the table Give your answers as decimals without rounding Watch Soccer Show Hints Yes No Yes Play Soccer No Total O UI 0 36

A city conducted a census to determine the types of schools attended by the city s students Hannah finds some of the data from the census on different websites and constructs the two way relative frequency table shown Use the table to complete the problem Grade Level Elementary Middle school High school Total Public non charter 26 6 23 2 16 2 66 0 Type of School Public charter 5 0 3 5 5 5 14 0 Private 6 4 5 3 8 3 20 0 Total 38 0 32 0 30 0 100 What is the probability expressed as a percentage that a student in the city attends a public non charter high school Enter the percent in the box Round to the nearest percent as needed

5 Yes No Total 7 Each region in the Venn diagram corresponds to a cell in the two way frequency table Yes 51 Play Soccer No 99 Total 96 9 54 150

Live in City Yes No 125 40 Total 165 Show Hints 65 Live in city 270 190 310 The two way frequency table of the data is given above Show how you can represent the data using a Venn diagram Fill in each blank with the correct frequency 335 500 Took public transit

ke a two way frequency table of the data shown in the Venn diagram Enter the frequencies in the table Grade Level Show Hints Freshman Sophomore Junior Senior Total Yes 53 27 19 167 Takes an Art Class No 124 583 Total 192 185 189 750

Live in the city took public transit 125 Live in the city took no public transit 65 Live outside the city took public transit 40 Live outside the city took no public transit 270 The photo shows the breakdown of responses Live in City Yes Live in City No Total Yes No Took Public Transit Yes No Total 125 Total 40 165 The two way frequency table of the data is given above Yes 0 25 65 0 08 270 0 33 335 190 Took Public Transit 310 500 No 0 13 0 54 0 67 Total 0 38 0 62 1 00

Live in City Yes No Total 165 Live in City 125 Yes 40 Show Hints No Total Make a two way relative frequency table of the data Enter the frequencies in the boxes Give your answers as decimals without rounding 65 270 Yes 190 310 335 500 Took Public Transit 0 33 No Total 0 38 0 62 1 00

2 Find a 95 confidence interval for the true mean of heights What is the interval Provide a Screenshot of your work from the t value Confidence Interval for u from the Confidence Interval tab on the Week 6 Excel spreadsheet Give a practi

Probability O 1 120 O 1 220 O 1 320 1 420 1 520 1 620 Permutation Formula n nP n r Number of Favorable Outcomes Total Number of Outcomes Combination Formula nC n n r r A math question has 6 steps and you must place them in order If you guess the order of the steps what is the probability you guess the correct order

O 1 10 1 5 1 20 1 40 Probability Permutation Formula n n r A You have 5 pair of flip flops A green pair a red pair a blue pair a whi pair and a black pain If you randomly select 3 pair to take on vacation what is the probability you choose the black white and red flip flops 1 45 O 1 60 of Favorable Outcomes Total Number of Outcomes Combination Formula n n r r nC

O 1 10 O 1 5 O 1 20 O 1 40 1 45 O 1 60 Permutation Formula n nPr n r A bucket contains the names of 10 people including you and your friend If 2 names are randomly selected find the probability the first name selected is yours and the second name selected is your friend s name 1 65 Combination Formula n Cr n r r

1 480 O 1 680 1 880 Permutation Formula n n r 1 1080 O 1 1280 Pr 1 1480 Probability If a lock code uses the digits 1 8 what is the probability the 4 digit code is 5555 Number of Favorable Outcomes Total Number of Outcomes Combination Formula n nC n r r