Statistics Questions

2 2 pts You wish to determine the average number of siblings everyone in our Statistics class has Describe what process you would go through to collect a sample if you use a systematic sample

1 2 pts A company that makes light bulbs would like to know what percentage of their light bulbs is defective when they leave their facilities They randomly select and test 100 of their light bulbs for defects Out of the light bulbs tested 4 of them did not work State the population and sample

4 2 pts A researcher has group listen to classical music while studying The other group studies in silence Grades are measured at end of the trial Is this a blind experiment double blind experiment or neither

2 The following are the Test 1 scores of my Calculus 3 classes in the last 3 semesters 3 26 40 62 74 88 5 63 74 89 13 53 64 74 89 64 77 90 67 79 90 83 91 13 14 27 27 25 29 31 17 32 47 60 68 18 34 48 60 69 84 91 19 35 49 61 70 85 94 21 36 50 61 73 85 95 37 51 62 73 87 96 52 41 52 45 46 46 b 2 Q 54 60 Data are sorted and rounded to the nearest unit for simplicity From the data find a 1 Median c 2 Q

Ruben is the proud owner of an eclectic bow tie collection He keeps track of how many bow ties he has and organizes them by pattern and material Velvet Cotton 3 1 Zigzags 4 Swirls 3 What is the probability that a randomly selected bow tie is made of cotton given that the bow tie is decorated with zigzags Simplify any fractions

Show the work neatly clearly systematically and understandably USE PROPER NOTATION Do as shown in MY class 1 14 1 2 2 2 3 4 Consider the following frequency distribution of a population X 17 18 19 20 21 f 18 22 20 11 9 a Find the mode b Find the median c Find Q d Find Q3 e Find the mean by extending the table above and then show your computation below

In a recent year about 36 of all infants born in a country were conceived through in vitro fertilization IVF Of the IVF deliveries about twenty five percent resulted in multiple births a Find the probability that a randomly selected infant was conceived through IVF and was part of a multiple birth b Find the probability that a randomly selected infant conceived through IVF was not part of a multiple birth c Would it be unusual for a randomly selected infant to have been conceived through IVF and to have been part of a multiple birth Explain

Question 8 Y The median home value in Indiana and Nevada adjusted for inflation are shown below Year Indiana Nevada 1950 37700 53700 2000 94300 142000 If we assume that the house values are changing linearly a In which state have home values increased at a higher rate Select an answer 0 b If these trends were to continue what would be the median home value in Indiana in 2010 Submit Question c If we assume the linear trend existed before 1950 and continues after 2000 the two states median house values will be or were equal in what year The answer might be absurd The year Question Help Video Message instructor

An insurance company believes that people can be divided into two classes those who are accident prone and tho who are not The company s statistics show that an accident prone person will have an accident at some time withi fixed 1 year period with probability 0 4 whereas this probability decreases to 0 16 for a person who is not accident prone Assume that 21 percent of the population is accident prone Some probabilities that can be found from this a included in the accompanying information What is the probability that someone has an accident in the second year given that they had no accidents in the first year Click the icon to view the probabilities NNN The probability is Type an integer or decimal rounded to four decimal places as needed

You collected the data given in the table below on y and x Complete an OLS regression using this data For credit show all your work Observation 1 2 3 y 5 4 10 1 Using calculus estimate coefficients for the following equation where a is the intercept b is the slope and e is the error term Hint be sure to consider both the FOC and SOC y a bx e O Obser 1 2 3 X 4 2 2 Write the estimated equation in numerical form 2 Fill in the following table using your estimated equation Cells with do not need to be calculated Two decimal places are enough 9 y Y 9 9 9

An urn contains 23 balls of which 15 are white Three players A B and C successively draw from the urn A first then B then C then A and so on The winner is the first one to draw a white ball Find the probability of winning for each player if a each ball is replaced after it is drawn b the balls that are withdrawn are not replaced a The probability that A wins is Simplify your answers the probability that B wins is and the probability that C wins is

Suppose a researcher collects data on the pollen allergen levels measured in grains per cubic meter in the morning and evening in 35 cities The data is plotted with morning pollen allergen levels on the horizontal axis and evening pollen allergen levels on the vertical axis Dayton Ohio is an outlier in the y direction What must be true about this city Select all true statements This city is an influential observation The evening pollen allergen level for this city is much higher or lower than other cities in the data set that have similar morning pollen allergen levels The morning pollen allergen level for this city is much higher or lower than the rest of the cities in the data set The evening pollen allergen level for this city is much higher or much lower than the rest of the cities in the data set The absolute value of the residual of this city is large

Two fair 14 sided dice are rolled What is the conditional probability that at least one lands on 8 given that the dice land on different numbers T The probability is Simplify your answer

A survey recently went out to 15 university presidents across a certain country The data represents the ages of the different presid Use a stem and leaf plot that has two rows for each stem to represent their ages 53 62 55 50 58 59 61 67 55 61 54 62 55 54 72

cannot have a negative acceleration Do you agree or disagree with this statement Justify your answer 17 What is the correct description of its motion during the ten second motion Baumgartner falls a Same distance every second b Further away every second c Less and less distance every second Even if Baumgartner doesn t have a parachute air resistance becomes important once he enters the denser layers of the atmosphere 18 List at least three factors that affect the air resistance of an object 19 Which of the following best explains how air resistance affects movement Air resistance caused it a decreased speed so that it takes less time to reach the ground b its speed decreased and it took more time to reach the ground c its speed increased and it took more time to reach the ground Module 3 Planning Parks Commercial playgrounds are big business and can cost schools up to 100 000 One of the most common playgrounds is the slide According to the CPSC Playground Safety Manual the target angle for fur and safety is between 30 45 degrees Dr Bookman chooses a 30 degree playground slide A 20 pound kindergartener plans to slide down the slide

A professor wanted to find a linear model that relates the number of hours a student plays video games each week h to the cumulative grade point average G of the student He obtained a random sample of 10 full time students at his college and asked each student to disclose the number of hours spent playing video games and the student s cumulative grade point average Complete parts a through f below Hours of Video Games per Week h O A Cumulative grade point average is being used to predict the number of hours B The number of hours and the cumulative grade point average are unrelated OC The number of hours is being used to predict cumulative grade point average OD The number of hours is directly related to the cumulative grade point average 4 DO23358812 0 0 10 Grade point Average G 3 39 2 95 3 14 2 72 3 59 2 68 2 21 2 94 1 93 2 91 a Explain why the number of hours spent playing video games is the independent variable and cumulative grade point average is the dependent variable Chong p answer below

Temperature 57 61 53 60 65 71 66 77 74 64 72 Ice Cream Sales 216 325 185 335 406 525 412 614 544 421 445 Use your calculator to find the line of best fit Round to two decimal places as needed Be sure to type in the entire equation Example y 4x 5 Type in the y too Try again Y 27 25X 1337 25 Edit my response If the temperature outside is 75 degrees how much would we expect to sell Round to the nearest dollar Submit

The average speed of a pitch in women s college fastpitch softball is 61 5 mph with a standard deviation of 2 5 mph Assume that the pitches are normally distributed What is the probability that a randomly selected pitch is between 60 mph and 65 mph 0 194 0 645 0 356

The distribution of lifetimes for a nickel metal hydride battery often found in hybrid vehicles is normally distributed with a mean of 90 000 miles and a standard deviation of 5 000 miles What is the probability that a nickel metal hydride battery will last more than 100 000 miles Round your answer to 3 decimal places A If you had 2 000 of these batteries how many would you expect to last more than 100 000 miles

93 liters is the same as how many gallons Hint 1 L 0 26 gal Round your answer to the nearest tenth

A dentist was making note of her upcoming appointments with different aged patients and the reasons for their visits Regular cleaning Broken tooth Toothache Patients under 18 Patients 19 60 2 3 6 2 5 4 What is the probability that a randomly selected appointment is for a broken tooth and is not with a patient under 18 Simplify any fractions

Temperature 57 61 53 60 65 71 66 77 74 Ice Cream Sales 216 325 185 335 406 525 412 614 544 421 Use your calculator to find the line of best fit Rour to two decimal places as needed Be sure to type in the entire equation Example y 4x 5 Type in the y too Submit If the temperature outside is 75 degrees how much would we expect to sell Round to the nearest dollar

The age at which babies walk is normally distributed with a mean of 13 months with a standard deviation of 1 5 months Which age separates the youngest 7 5 that walked 9 4 months 14 months 10 8 months 14 9 months

A survey among seniors at a large university revealed that the number of hours spent studying the week before final exams was normally distributed with a mean of 30 hours and a standard devation of 7 What percent of seniors spent less than 25 hours studying Round your to 1 decimal place

Solve for b 11 b 2 12 Write your answer as a fraction or as a whole or mixed number b

1 41 mogb33dn som non bobogans6 835 mmmbno bnbogasan 1 10 2 10000 3 41 42 Morbanan m honns dsan6 xy 3z 3

Simplify Rationalize the denominator 2 2 C

How many gallons are there in 44 liters Hint 1 L 0 26 gal Round your answer to the nearest tenth

The magnitude of a vector d is 9 and its direction angle 8 is 11 Write the component form for d Round each component to the nearest hundredth d

Write the vector in component form 104 10 8 6 4 2 8 6 4 2 0 2 4 6 8 10 2 4 6 LO 8 X 10

What is the area of this figure 11 yd 7 yd 6 yd 5 yd 9 yd 3 yd 15 yd 3 yd Write your answer using decimals if necessary square yards

Assume random variable X follows a normal distribution with mean 50 and standard deviation of 10 a Use the Empirical rule to find P 40 X 60 Write as a probability not as a percentage 0 68 b Use the Empirical rule to find P 40 X 50 Write as a probability not as a percentage 0 34 c Use the Empirical rule to find P 30 X 50 Write as a probability not as a percentage d Use the Empirical rule to find P X 80 Write as a probability not as a percentage e Use the Empirical rule to find P 20 X 60 Write as a probability not as a percentage

Based on the following calculator output determine the inter quartile range of the dataset 1 Var Stats x 200 857142857 Ex 1406 x 285616 Sa 23 1331549328 0x 21 4171398079 n 7 minX 168 Q 184 Med 197 Q3 211 maxX 241

22 The equivalent resistance of a complex circuit is usually determined by a inspection b simplifying the circuit into groups of series and parallel circuits c adding and subtracting individual resistances d dividing the sum of the individual resistances by the number of resistances

Seth plays in a hockey league His team is called the Broncos Each team in the league has 20 players The table below shows the number of points each player on Seth s team collected this season The two tables represent the points each player collected on two other teams in Seth s league Which team has a mean that is of the mean absolute deviation more than the mean of the Broncos Note the mean absolute deviation for all three data sets is the same 1 0025 8 8 15 18 19 26 26 28 32 33 33 38 40 41 58 70 Storm 24 1 4 5 6 10 12 15 21 22 27 35 35 35 36 39 80 10 Raptors 4 4 8 10 18 18 18 19 25 26 30 31 32 33 35 40 42 51 76 80

D D A survey recently went out to 15 university presidents across a certain country The data represents the ages of the different presidents Use a stem and leat plot that has two rows for each stem to represent their ages 53 63 59 53 56 58 60 69 55 63 54 62 57 54 71 Determine the leaves in the stem and leaf plot shown at the right Use ascending order Which of the following best summarizes what the stem and leaf plot tells you about the data OA The plot shows that most university presidents have ages that range from 65 to 75 years old OB The plot shows that most university presidents have ages that range from 50 to 65 years old OC The plot shows that the age of the university presidents cluster around age 60 OD The plot shows that there is an equal amount of university presidents under the age of 60 as there is above the age of 60 GOLD Stems 5 5 8 Leaves

B Wheh meseure of certer bemer describes the typical number of hours the seniors work per week Explain 4 The following cumulative relative frequency graph displays the distribution of the lifetime in hours of a AA battery 1 Lifetimes of AA Batteries hrs r e O m 0 9 U 1 0 8 q V e 0 5 0 4 r e 0 3 1 0 2 0 1 1 0 7 t 1 10 6 T I 1 4 H L 1 T L I 4 I 1 L T 1 44 0 150 175 200 225 250 275 300 325 350 375 400 Battery Life in hours a Approximately what percent of the batteries will last fewer than 250 hours Approximately what proportion of batteries will last 325 hours or more

emale ale otal reach each level of attainment The National Center for Educational Statistics provides projections for the number of de grees earned classified by level and by the sex of the degree recipient Here are the projected number of earned degrees in thousands in the United States for the 2019 2020 academic year 7 Associate s Bachelor s Master s Doctorate Total 756 1143 589 99 2587 519 792 349 98 1758 1275 1935 938 197 4345 a If you choose a degree recipient at random what is the probability that the person you choose is a man b What is the conditional probability that you choose a man given that the person chosen received a master s

5 Lost Internet Sites Internet sites often vanish or move so that references to them can t be followed In fact 13 of Internet sites referenced in major scientific journals are lost within two years after publication If a paper contains seven Internet references what is the probability that all seven are still good two years later What specific assumptions did you make to calculate this probability

49 Winning at tennis A player serving in tennis has two chances to get a serve into play If the first serve is out the player serves again If the second serve is also out the player loses the point Here are probabilities based on four years of the Wimbledon Championship 20 P 1st serve in 0 59 P win point 1st serve in 0 73 P 2nd serve in 1st serve out 0 86 P win point 1st serve out and 2nd serve in 0 59 Make a tree diagram for the results of the two serves and the outcome win or lose of the point The branches in your tree have different numbers of stages depending on the outcome of the first serve What is the probabil

11 Independent In 2015 the Report on the UC Berkeley Faculty Salary Equity Study shows that 87 of the university s 222 assistant professors were women along with 137 of the 324 associate professors and 243 of the 972 full professors a What is the probability that a randomly chosen Berkeley professor of any rank is a woman b What is the conditional probability that a randomly chosen professor is a woman given that the person chosen is a full professor c Are the rank and sex of Berkeley professors independent How do you know

3 1 Photo and Video Sharing Photos and videos have become an important part of the online social experience with more than half of Internet users post ing photos or videos online that they have taken themselves Let A be the event an Internet user posts photos that he or she has personally taken and B be the event an Internet user posts videos that he or she has personally taken Pew Research Center finds that P A 0 52 P B 0 26 and P A or B 0 54 a Make a Venn diagram similar to Figure 13 4 showing the events A and B A and not B B and not A and neither A nor B b Describe each of these events in words c Find the probabilities of all four events and add the probabilities to your Venn diagram The four probabilities you have found should add to 1

3 9 At the Gym Suppose that 8 of adults belong to health clubs and 45 of these health club members go to the club at least twice a week What percent of all adults go to a health club at least twice a week Write the information given in terms of probabilities and use the general multiplication rule

3 3 Older College Students Government data show that 8 of adults are full time college students and that 25 of adults are aged 55 or older Nonetheless we can t conclude that because 0 08 0 25 0 02 about 2 of adults are college students 55 or older Why not

3 53 Lactose intolerance Lactose intolerance causes diffi culty digesting dairy products that contain lactose milk sugar It is particularly common among people of African and Asian ancestry In the United States ignor ing other groups and people who consider themselves to belong to more than one race 82 of the popula tion is white 14 is black and 4 is Asian Moreover 15 of whites 70 of blacks and 90 of Asians are lactose intolerant 22 a What percent of the entire population is lactose intolerant b What percent of people who are lactose intolerant

29 Universal blood donors People with type O negative blood are referred to as universal donors although if you give type O negative blood to any patient you run the risk of a transfusion reaction due to certain antibodies present in the blood However any patient can receive a transfusion of O negative red blood cells Only 7 2 of the American population have O negative blood If 10 people appear at random to give blood what is the prob ability that at least one of them is a universal donor

8 15 False Negative Rate In a diagnostic test for a particular disease the condi tional probability that a person has the disease given that the test is negative is called the false negative rate Suppose the PSA screening test with the prop erties described in Example 13 14 is used to screen for prostate cancer in the population of men over 50 for which 6 3 have prostate cancer Compute the false negative rate using Bayes rule

1 Billed customers for fees earned 57 620 2 Purchased supplies on account 2 480 3 Received cash from customers on account 54 160 4 Paid creditors on account 1 500 a Journalize these transactions in a two column journal using the appropriate number to identify the transactions Journal entry explanations may be omitted If an amount box does not require an entry leave it blank 1 Accounts Receivable Fees Earned 2 Supplies Accounts Payable 3 Cash V Accounts Receivable 4 Accounts Payable Cash V Feedback 00 00 00 00 00 00 00 Check My Work a Identify the type of accounts affected in each transaction Determine whether the account increases or decreases and record each increase or decrease following the rules of debit and credit Remember total debits should equal total credits in your entries b Post the entries prepared in a to the following T accounts Cash Supplies Accounts Receivable Accounts Payable Fees Earned To the left of each amount posted in the accounts select the appropriate number to identify the transaction Cash 4 Accounts Payable 2 Supplies Fees Earned V

n 200 p 375 a Find the Mean Standard Deviation P x 22 b Assuming Poisson distribution Mean 40 What is the probability x 3 6

Determine the probability of the given complementary event What is the probability that a 59 free throw shooter will miss her next free throw The probability that a 59 freethrow shooter will miss her next free throw is Type an integer or a decimal