# Lower/Upper Bound

An article reports that when each football helmet in a random sample of 44 suspension-type helmets was subjected to a certain impact test, 25 showed damage.

Let p denote the proportion of all helmets of this type that would show damage tested in the prescribed manner

Give your answers correct to three decimal places

Calculate the lower bound for a 99% confidence interval for p

Give your answers correct to three decimal places.

Calculate the upper bound for a 99% confidence interval for p.

Give the exact answer

Calculate the sample size that would be required for the width of a 99% confidence interval to be at most 0.2? Use phat=1/2 to get the most conservative sample size.

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#### Solution Preview

An article reports that when each football helmet in a random sample of 44 suspension-type helmets was subjected to a certain impact test, 25 showed damage.

Let p denote the proportion of all helmets of this type that would show damage tested in the prescribed manner

Give your answers correct to three decimal places

Calculate the lower bound for a 99% confidence interval for p

Solution. The sample mean of the ...

#### Solution Summary

This solution calculates an upper and lower bound with a given confidence interval for p.