Question

When trying to forecast revenue, an employee knows from the past 36 weeks that the average amount of revenue a company receives is $37,654 with a standard deviation of $4,198. Calculate the upper bound of the 85% confidence interval for the average revenue. (please round your answer to 1 decimal place)

Answer 1

Solution :

degrees of freedom = n - 1 = 36 - 1 = 35

t,df = t_0.15,35 = 1.052

Margin of error = E = t_,df * (s /n)

= 1.052 * ( 4198 / 36)

Margin of error = E = 736.0

The 85% upper confidence interval estimate of the population mean is,

+ E  

= 37654 + 736.0 = 38390.0

upper bound = $ 38,390.0