Author:
Christine Farr

1)The time spent (in days) waiting for a heart transplant for people ages 35-49 can be approximiated by the normal distribution, as shown in the figure to the right.

(a) What waiting time represents the 20th percentile?

(a) What waiting time represents the third quartile?

2)The time spent (in days) waiting for a kidney transplant for people ages 35-49 can be approximiated by the normal distribution, as shown in the figure to the right.

(a) What waiting time represents the 98th percentile?

(b) What waiting time represents the first quartile?

Find the probability and interpret the results. If convenient, use technology to find the probability.

3)The population mean annual salary for environmental compliance specialists is about $62 comma 500. A random sample of 34 specialists is drawn from this population. What is the probability that the mean salary of the sample is less than $59, 000? Assume sigma equals$5 comma 700.The probability that the mean salary of the sample is less than $59, 000 is

4)The mean height of women in a country (ages 20-29) is 64.2 inches. A random sample of 50 women in this age group is selected. What is the probability that the mean height for the sample is greater than 65 inches? Assume sigma equals2.83.

5)A manufacturer claims that the life span of its tires is 49, 000miles. You work for a consumer protection agency and you are testing these tires. Assume the life spans of the tires are normally distributed. You select 100 tires at random and test them. The mean life span is 48, 773 miles. Assume sigma equals700.

Complete parts (a) through (c).

(a) Assuming the manufacturer's claim is correct, what is the probability that the mean of the sample is 48, 773 miles or less?

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