Question

Annual starting salaries for college graduates with degrees in business administration are generally expected to be between $10,000 and $35,000. Assume that a 95% confidence interval estimate of the population mean annual starting salary is desired. Given the information in the Microsoft Excel Online file below, construct a spreadsheet to determine how large a sample should be taken for each desired margin of error.Starting Salary Desired margin of errorA. Lower 10000B. Upper 35000Desired Margin of errorA. 300B. 170C. 100

Answer 1

a ) n = 1667

b) n= 5192

c) n=1500

Explanation:

c= 95%

Expected value = E.v= 300 , 170 , 100

R = 35000-10000=25000

σ = R / 4 = 25000 / 4 = 6250

For sample size

b = ( zα/2 / 2σ / E )^2

where 1-α = 0.95 and

zα/2 = 1.96

then putting values one by one of E we get

E.v = 300

n= 1667

E.v = 170

n=5192

E.v =100

n= 1500

so for

a ) n = 1667

b) n= 5192

c) n=1500