Question

Salaries of 4747 college graduates who took a statistics course in college have a​ mean, x overbarx​, of $63,000. Assuming a standard​ deviation, sigmaσ​, of ​$16 comma 37216,372​, construct a

9090​% confidence interval for estimating the population mean μ.

​(Round to the nearest integer as​ needed.)

Answer 1

Solution :

Given that,

Point estimate = sample mean = = 63000

Population standard deviation = = 16372

Sample size = n = 47

Z_/2 = 1.645

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

= 1.645 * (16372 / 47)

= 3928

At 90% confidence interval estimate of the population mean is,

- E < < + E

63000 - 3928 < < 63000 + 3928

59072 < < 66928

(59072 , 66928 )