Question

According to a Pew Research Center study, in May 2011, 43% of all American adults had a smart phone (one which the user can use to read email and surf the Internet). A communications professor at a university believes this percentage is higher among community college students. She selects 405 community college students at random and finds that 196 of them have a smart phone. Then in testing the hypotheses:

H0: p = 0.43 versus

Ha: p > 0.43,

what is the test statistic?

z = ?(Please round your answer to two decimal places.)

Answer 1

Solution :

Given that,

= 0.43

1 - = 0.57

n = 405

x =196

Point estimate = sample proportion = = x / n = 0.484

This a right (One) tailed test.

Test statistics

z = ( - ) / *(1-) / n

= ( 0.484 - 0.43) / (0.43*0.57) / 405

= 2.19

z = 2.19