Dog bites to postal workers for a certain urban area, in a random sample of 5 months, an average of 28 mail carriers were bitten by dogs each month. the standard deviation of the sample was 3. find the 90% confidence interval of the true mean number of mail carriers who are bitten by dogs each month. assume the variable is normally distributed.

90% confidence interval is (25.8,30.2).

Step-by-step explanation:

Since we have given that

n = 5

Mean = 28

Standard deviation = 3

It is a 90% confidence interval , so, z = 1.64

We need to find the interval.

so, it would be

Hence, 90% confidence interval is (25.8,30.2).

answer: .64

step-by-step explanation

set up the formula for standard deviation for this set of numbers, then simplify