Question

A study was commissioned to find the mean weight of the residents in certain town. The study examined a random sample of 123 residents and found the mean weight to be 187 pounds with a standard deviation of 21 pounds. Determine a 95% confidence interval for the mean, rounding all values to the nearest 10th. (let z=2)

Answer 1

Explanation:

The formula:

`mean+/-z(s)/(√(n) )`

mean = 187

z = 2

s = 21

n = 123

`187+2(21)/(√(123) )` and
`187-2(21)/(√(123) )`

190.79 and 183.21

Answer is between 183.21 - 190.79