Question

A survey​ asked, "How many tattoos do you currently have on your​ body?" Of the 1233 males​ surveyed, 185 responded that they had at least one tattoo. Of the 1028 females​ surveyed, 132 responded that they had at least one tattoo. Construct a 99​%confidence interval to judge whether the proportion of males that have at least one tattoo differs significantly from the proportion of females that have at least one tattoo. Interpret the interval.

Let p1 represent the proportion of males with tattoos and p2 represent the proportion of females with tattoos. Find the 99​% confidence interval for p1−p2.

The lower bound is _______ .

The upper bound is ______ .

Interpret this value.

Answer 1

We know that the 99% confidence interval for difference of proportions is given by:

Since this interval contains the value 0, there isn't sufficient evidence to conclude that the two proportions differ.