Question

(Question 14) 2 pts In a survey of first graders, their mean height was 51.6 inches with a standard deviation of 3.6 inches. Assuming the heights are normally distributed, what height represents the first quartile of these students? 54.03 inches 49.17 inches 48.00 inches 48.57 inches Flag this Question

(Question 15) 2 pts Hospital waiting room times are normally distributed with a mean of 38.12 minutes and a standard deviation of 8.63 minutes. What is the shortest wait time that would still be in the worst 5% of wait times? 46.75 minutes 52.32 minutes 29.49 minutes 23.92 minutes

Answer 1

(Question 14) 2 pts In a survey of first graders, their mean height was 51.6 inches with a standard deviation of 3.6 inches. Assuming the heights are normally distributed, what height represents the first quartile of these students?

54.03 inches

Answer: 49.17 inches

48.00 inches

48.57 inches

z value for first quartile = -0.674

x = mean+z*sd = 51.6-0.674*3.6 = 49.17

(Question 15) 2 pts Hospital waiting room times are normally distributed with a mean of 38.12 minutes and a standard deviation of 8.63 minutes. What is the shortest wait time that would still be in the worst 5% of wait times?

46.75 minutes

52.32 minutes

29.49 minutes

Answer: 23.92 minutes

z value for lower 5% = -1.645

x = mean+z*sd = 38.12-1.645*8.63 = 23.92