In Exercises 5–20, assume that the two samples are independent simple random samples selected from
18. Car and Taxi Ages When the author visited Dublin. Ireland (home of Guinness Brewery employee William Gosset, who first developed the t distribution), he recorded the ages of randomly selected passenger cars and randomly selected taxis. The ages can be found from the license plates. (There is no end to the fun of traveling with the author.) The ages (in years) are listed below. We might expect that taxis would be newer, so test the claim that the
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Essentials of Statistics (6th Edition)
- QUESTION 2 Use the 68-95-99.7 rule to solve the problem. Scores on a test are normally distributed with a mean of 102 and a standard deviation of 16. What percentage of scores are greater than 134? O 97.5% 95% O 5% 2.5%arrow_forwardWhen you have a certain blood test done, the phlebotomist takes 3 vials of blood that hold 10 mL each. Obviously, there is variability in the amount of blood that actually goes in to the vials. (a) Five vials are selected randomly from a day's batch, and the amount of blood (in mL) in each vial is measured and recorded. The results are as follows. 9.61, 9.65, 9.68, 9.81, 9.93 What is the mean amount (in mL) of blood in the vials? mL (b) When you donate blood, you give between 450 and 500 mL. Five randomly selected samples of blood donations were selected, and the amount of blood (in mL) in each was measured and recorded. The results are as follows. 454, 457, 461, 474, 495 What is the mean amount (in mL) of blood in the donations? mL (c) What is the median (in mL) of the five samples of blood donations from part (b)? mLarrow_forward2. Explain the term variability (this is not asking for a definition).arrow_forward
- State the formula for Variance.arrow_forwardcalculate the mean, median, mode, variance and standard deviationarrow_forwarddo question 4, 5 and 6 only The new study claims that the probability of contracting the winter flu among vaccinated high school children is less than 0.5. Assume that p is the population proportion of vaccinated high school children who contract the flu. The appropriate framework to test the new study's claim is H0:p>0.5 vs H1:p<0.5 H0:p=0 vs H1:p≠0 H0:p=0 vs H1:p>0 H0:p=0.5 vs H1:p<0.5 Question 4 The new study takes a random sample of 14 vaccinated high school children. Let x be the number of children in the sample who contract the flu. The p-value for the test can be calculated from a Binomial distribution using P(X≤x). The maximum number of children who can contract the flu to give evidence against the null hypothesis in Question 3 at the 5% level is 1 2 3 5 Question 5 Suppose the actual population proportion of vaccinated high school children who contract the flu is 30%. For a random sample of 14 vaccinated high school children and based on your answer to Question 4,…arrow_forward
- QUESTION 1 A supermarket has two customers waiting for their purchases at counter 1 and one customer waiting to pay at counter 2. Let X1 and X2 denote the numbers of customers who spend more than RM50 on groceries at the respective counter. Suppose that X1 and X2 are independent binomial random variables, with the probability that a customer at counter I will spend more than RM50 equal to 0.2 and the probability that a customer at counter 2 will spend more than RM50 equal to 0.3.arrow_forwardsolve question 3.2 with explanation and get upvotesarrow_forwardQuestion 2, section 6.1arrow_forward
- Q.1 Suppose samples are taken from a population of heifers with known mean and variance of weight gains of 188 lbs. and 2200 square lbs., respectively. a) What are the mean and the variance of an average weight gain estimated from a sample of 20 heifers? (188,110) b) What are the mean and variance from a sample of 30 heifers? (188, 73.3) c) How many heifers should be in a sample in order for the variance of sample means to equal 50? (44)arrow_forwardQUESTION 3 Mr. Jones believes that the mean income of lawyers has changed and is no longer $65 thousand per year. Which is the correct set of hypotheses to test this belief? O Ho:p 2 65,000; Ha: µ 65, 000 O Ho:u = 65, 000; Ha: µ + 65, 000 Ho:p 65, 000 O Ho:u = 65, 000; Ha: µ > 65, 000arrow_forwardII. Solve for the variance and standard deviation. b. 6 9. 12 15 Р() 0.02 ? 0.27 0.18 0.15arrow_forward
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill