5. Suppose a tire company developed two new brands of tires and would like to compare the variability of the tire life of the two. Both brands were driven under normal conditions, and random samples of the tires were collected. The table below shows the sar sizes and the standard deviations, in miles, calculated for each sample. Complete parts a and b. Brand 1 Brand 2 Sample standard deviation Sample size 3,700 miles 3,300 miles 30 30 a. Using a = 0.10, determine if there is a difference in the variability of the two tire brands. Identify the null and alternative hypotheses. Ho: o? (1) H,: o? (2) Calculate the appropriate test statistic.

(5). Calculate SS, variance and standard deviation for the following sample of n=7 scores: 8, 6, 5, 2, 6, 3, 5.

A researcher takes sample temperatures in Fahrenheit of 17 days from New York City and 18 days from Phoenix. Test the claim that the mean temperature in New York City is different from the mean temperature in Phoenix. Use a significance level of α=0.05. Assume the populations are approximately normally distributed with unequal variances. You obtain the following two samples of data. New York City Phoenix 99 94.2 95.5 72 93.2 86.8 102 122.1 85.4 114.4 80 94.7 86.4 89.7 75.4 104.7 79.5 77.6 83.4 106.8 64.3 98.6 65.5 91.5 87.7 82 104 97.7 74.3 64.9 59.5 82 82.8 72   116.2 The Hypotheses for this problem are: H0: μ1 = μ2 H1: μ1μ2 Find the p-value. Round answer to 4 decimal places. Make sure you put the 0 in front of the decimal. p-value =

Two accounting professors decided to test if the variance of their grades is different or no. To accomplish this, they each graded the same 10 exams with the following results: Standard Deviation 22.4 Mean Grade Professor 1 79.3 Professor 2 82.1 12.0 F What is the P-value of the test? Select one: a. between 0.01 and 0.025 Ob. between 0.025 and 0.05 C. between 0.05 and 0.10 Od. bigger than 0.10