Let

be the mean of

. Then

For a random variable

following the standard normal distribution, we have

Transform the random variable to get this critical value in terms of

:
If she is driving at 30 miles a hour it takes two minutes to cover a mile 60 divided by 30
if she is driving at 2 minutes a mile and is going 24 miles it will take 48 minutes
2*24 =48
solution she is a slow driver she needs to pick up the pace or she will be 3 minutes late to work
45-48=-3

<u>Answer</u><u>:</u>
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