Question

A marketing manager for a cell phone company claims that the percentage of children aged - who have cell phones differs from . In a survey of children aged - by a national consumers group, of them had cell phones. Can you conclude that the manager's claim is true

Answer 1

Yes, the marketing manager's claim is true.

Explanation:

p = 0.61

Phat = 545 /826 = 0.66

H0 : p = 0.61

H1 : p ≠ 0.61

The test statistic :

(Phat - p) / √pq/n

q = 1 -p = 1 - 0.61 = 0.39

(0.66 -0.61) / √(0.61*0.39)/826

0.05 / 0.0169709

Test statistic = 2.95

Using the p-value from Zscore calculator:

Pvalue at 2.95, two tailed ;

Pvalue = 0.0032

Reject H0; if Pvalue < α

Since, Pvalue < α ; Then, the marketing manager's claim is true