Question

1) A leading magazine (like Barron's) reported at one time that the average number of weeks an individual is unemployed is 15.8 weeks. Assume that for the population of all unemployed individuals the population mean length of unemployment is 15.8 weeks and that the population standard deviation is 9.5 weeks. Suppose you would like to select a random sample of 22 unemployed individuals for a follow-up study.

Find the probability that a single randomly selected value is between 19 and 20.7. P(19 < X < 20.7) =

Find the probability that a sample of size n = 22 n = 22 is randomly selected with a mean between 19 and 20.7. P(19 < M < 20.7) =

2)CNNBC recently reported that the mean annual cost of auto insurance is 995 dollars. Assume the standard deviation is 146 dollars. You will use a simple random sample of 138 auto insurance policies.

Find the probability that a single randomly selected policy has a mean value between 960.2 and 976.4 dollars.
P(960.2 < X < 976.4) =

Find the probability that a random sample of size n=138n=138 has a mean value between 960.2 and 976.4 dollars.
P(960.2 < M < 976.4) =

Enter your answers as numbers accurate to 4 decimal places.

Answer 1