SOLUTION: The life span of a calculator batter is normally distributed with a mean of 45 and a standard deviation of 4 hours. What is the probability that a battery last more than 50 hours

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Question 1057327: The life span of a calculator batter is normally distributed with a mean of 45 and a standard deviation of 4 hours. What is the probability that a battery last more than 50 hours?
Answer by solve_for_x(190) About Me  (Show Source):
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Calculate the z-score:

z = (x - µ) / σ

z = (50 - 45)/4 = 1.25

Then use a table of the normal distribution, or Excel, or a statistical calculate to determine the area under the normal curve to the right of z = 1.25:

P(x > 50) = P(z > 1.25) = 0.1056