In a sample of 50 iPhones, 13 had over 100 apps downloaded. Construct a 99% confidence interval for the population proportion of all iPhones that obtain over 100 apps. Assume z_0.005 = 2.576. A) 0.13± 0.16 B) 0.13± 0.09 C) 0.26± 0.15 D) 0.26± 0.16

Question

Quizplus · Accepted Answer

The sample proportion is 0.26 (13/50). The standard error is calculated as sqrt[(0.26)(0.74)/50]. The margin of error is 2.576 times the standard error. The confidence interval is 0.26 ± 0.16.

In a Sample of 50 IPhones, 13 Had Over 100