Problem
QUESTION 12 Find the critical value \( t_{C} \) for a \( 99 \% \) confidence level when the sample size is 23 A. 2.074 B. 2.069 C. 2.819 D. 2.807 QUESTION 13 An economist found that a random sample of 45 high school teachers had an average annual salary of \( \$ 58,230 \). A previous study st Standard deviation is \( \$ 4450 \). Calculate the margin of error, E, for a \( 90 \% \) confidence interval for \( \mu \), the average annual salary of all hig B. \( \$ 1091.2 \) C. \( \$ 1300.2 \) D. \( \$ 1652.1 \) QUESTION 14 Let \( x \) be a random variable that represents the commute time of teachers in a large urban area. If \( x \) is normally distributed with a mean of standard deviation of 5.2 minutes, find the commute time which is at the top of the bottom \( 10 \% \). A. 41.38 minutes B. 42.63 minutes C. 42.34 minutes D. 55.66 minutes Click Save and Submit to save and submit. Click Save All Answers to save all answers. Type here to search
Solution
Step 1 ：\(t_{C} = 2.807 \)
Step 2 ：\(E = \$ 1091.2 \)
Step 3 ：\(x = 42.63 \; \text{minutes} \)
