SOLUTION: A recent study found that the average life expectancy of a person living in X-country is 55 years with a standard deviation of 8 years. If a person in X-country is selected at rand

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Question 1089617: A recent study found that the average life expectancy of a person living in X-country is 55 years with a standard deviation of 8 years. If a person in X-country is selected at random, what is the probability that the person will die between the age of 60 - 65?
a. 0.1056

b. 0.7521

c. 0.8944

d. 0.1587
Answer by reviewermath(1029) About Me  (Show Source):
You can put this solution on YOUR website!

For x = 60:
z = (60-55)/8 = 0.625 or 0.63
For x = 65:
z = (65 - 55)/8 = 1.25
From Normal table
http://www.itl.nist.gov/div898/handbook/eda/section3/eda3671.htm
P(0 to 0.63) = 0.23565 and P(0 to 1.5) = 0.39435
Hence, P(60 < X < 65) =0.39435 - 0.23565 = highlight%280.1587%29