# Normal distribution - Probability

Suppose that the time required to complete a 1040R tax form is normally distributed with a mean of 100 minutes and a standard deviation of 20 minutes. What proportion of 1040R tax forms will be completed in less than 60 minutes? Round your answer to at least four decimal places.

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#### Solution Preview

Mean = 100 minutes

Standard Deviation = 20 minutes

X = 60 minutes

Z score = (X-Mean)/Standard deviation = ...

#### Solution Summary

The solution shows how to calculate the probability using normal distribution.

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