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In: Statistics and Probability

The pregnancy length in days for a population of new mothers can be approximated by a...

The pregnancy length in days for a population of new mothers can be approximated by a normal distribution with a mean of 266 days and a standard deviation of 8 days. ​(a) What is the minimum pregnancy length that can be in the top 11​% of pregnancy​ lengths? ​(b) What is the maximum pregnancy length that can be in the bottom 4​% of pregnancy​ lengths?

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Expert Solution

Answer:

Given that:

The pregnancy length in days for a population of new mothers can be approximated by a normal distribution with a mean of 266 days and a standard deviation of 8 days

a) What is the minimum pregnancy length that can be in the top 11​% of pregnancy​ lengths?

The distribution of the 11% is

Using Z -score formula

The minimum pregnancy length is 275.8 days

b) What is the maximum pregnancy length that can be in the bottom 4​% of pregnancy​ lengths?

The distribution of the 4% is

Using Z -score formula

The minimum pregnancy length is 251.9 days

orchestra answered 2 years ago
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