Question

Salaries of 38 college graduates who took a statistics course in college have a mean, x, of $66,100. Assuming a standard deviation, o, of $15,100, construct a 95% confidence interval for estimating the population mean u

$___<u<$___

Answer 1

Solution :

Given that,

= 66100

= 15100

n = 38

At 95% confidence level the z is ,

= 1 - 95% = 1 - 0.95 = 0.05

/ 2 = 0.05 / 2 = 0.025

Z_/2 = Z_0.025 = 1.96

Margin of error = E = Z_/2* ( /n)

= 1.96 * (15100 / 38)

= 4801

At 95% confidence interval estimate of the population mean is,

- E < < + E

66100 - 4801 < < 66100 + 4801

$61299 < < $70901