Question

The weights for a population of North American raccoons have a bell-shaped frequency curve with a mean of about 12 pounds and a standard deviation of about 2.5 pounds. About 95% of the weights for individual raccoons in this population fall between what two values?

Answer 1

Explanation:

Given that the weights for a population of North American raccoons have a bell-shaped frequency curve with a mean of about 12 pounds and a standard deviation of about 2.5 pounds

Since bell shaped is given we can assume that this follows a normal distribution symmetrical about the mean.

To find 95% two values we can use Z critical value for 95%

i.e. ±1.96

95% will lie between 12±1.96(2.5)

= 12±4.9

=(7.1, 16.9)