Question

Choose the best answer.
Do you own an iPod Nano or a Sony Walkman Bean? These and other brands of MP3 players are becoming more and more popular among younger Americans. An iPod survey reported that 54% of 12- to 17-year-olds, 30% of 18- to 34-year-olds, and 13% of 35- to 54-year-olds own MP3 players. Suppose that these three estimates are based on random samples of size 400, 350, and 362, respectively.
A. Construct a 95% confidence interval estimate for the proportion of 12- to 17-year-olds who own an MP3 player.
B. Construct a 95% confidence interval estimate for the proportion of 18- to 34-year-olds who own an MP3 player.

Select one:

A. 0.54 ± 0.0024
B. 0.30 ± 0.0026

A. 0.54 ± 0.0488
B. 0.30 ± 0.0480

A. 0.54 ± 0.0012
B. 0.30 ± 0.0012

A. 0.54 ± 0.0720
B. 0.30 ± 0.0574

Answer 1

A)

from above:

95% confidence interval estimate for the proportion of 12- to 17-year-olds who own an MP3 player =0.54 -/+ 0.0488

B)

\95% confidence interval estimate for the proportion of 18- to 34-year-olds who own an MP3 player =0.30 -/+ 0.0480