# Probability from Z score

The lifetime of a super tough AAA battery is normally distributed wit mean of 28.5 hours and standard deviation of 5.3 hours. For a battery selected at random, what is the probability that the lifetime will be? Use given data, requirement and sketch of normal curve labled to solve;

a) 25 hours or less

b) 34 hours or more

c) between 25 and 34 hours

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The lifetime of a super tough AAA battery is normally distributed wit mean of 28.5 ...

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This solution gives the step by step method for computing probabilities based on Z score.

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