SOLUTION: The XYZ Company tested a new product and found its lifetime to be normally distributed, with a mean life of 146 days and a standard deviation of 19.5 days. What is the probability

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Question 316509: The XYZ Company tested a new product and found its lifetime to be normally distributed, with a mean life of 146 days and a standard deviation of 19.5 days. What is the probability that a product selected at random will last longer than 166 days?
Answer
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Find the zscore.
z=%28x-mu%29%2Fsigma=%28166-146%29%2F19.5
z=1.026
P%281.026%29=0.84747
The probability is for x%3C=166
P(x%3C=166)+P(x%3E166)=1
P(x%3E166)=1-P(x%3C=166)
P(x%3E166)=1-0.84747
P(x%3E166)=0.15253