Question

A marketing manager in the phone company hypothesized that the

proportion of smartphone users in a city was 20%. A survey was conducted

and analyzed. You were given the calculated Z value from the hypothesis test

as 7.5. Does it support the manager’s hypothesized view?

Answer 1

Let us define the null and alternative hypothesis:

Ho: Proportion of smartphone users in a city was 20%.,I.e p=0.30

Ha: Proportion of smartphone users in a city was not 20%. ,I.e p not equal to 0.20

Here given that Z=7.5

Let us assume level of significance is 0.05.Since the value of critical at the 0.05 level of significance is 1.96.

Critical value =1.96

Decision rule :

Since ,Observed test statistic =7.5 >critical value =1.96,Thus we reject the null hypothesis.It is not support the managers hypothesized view.

Therefore it is conclude that proportion of smartphone users in a city was not 20%.