# statistics

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The lifetime of a 2- volt non- rechargeable battery in constant use has a normal distribution with a mean of 516 hours and a standard deviation of 20 hours. What is the z-score for batteries with lifetimes of 600 hours?

• statistics -

Use z-scores.

Formula:
z = (x - mean)/sd

z = (600 - 516)/20

I'll let you finish the calculation.

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