Question

4. The amount of time in hours that college students spend on facebook per week is normally distributed with a mean of 40. You decide to conduct your own test. In a random sample of 60 college students you find that the mean time per week spent on facebook is 37.8 hrs and the standard deviation is 12.2. Does this mean differ significantly from the national average? Test your hypothesis at the .05 significance level and state your conclusion.

Answer 1

Solution :

= 40

=37.8

S =12.2

n = 60

This is the two tailed test .

The null and alternative hypothesis is ,

H₀ :    = 40

H_a :     40

Test statistic = t

= ( - ) / S / n

= (37.8-40) / 12.2/ 60

= −1.397

Test statistic = t =  −1.397

P-value =0.1677

= 0.05  

P-value >

0.1677 > 0.05

Fail to reject the null hypothesis .

There is not sufficient evidence to claim that the population mean μ is different than 40, at the 0.05 significance level.