Lying online Many teens have posted profiles on sites such as Facebook. A sample survey asked random samples of teens with online profiles if they included false information in their profiles. Of 170younger teens (ages role="math" localid="1654194610029" 12to14) polled, 117said “Yes.” Of 317older teens (ages 15to17) polled, 152said “Yes.” A 95%confidence interval for pY-pO=the true difference in the proportions of younger teens and older teens who include false information in their profile is 0.120to 0.297.

a. Interpret the confidence interval.

b. Does the confidence interval give convincing evidence of a difference in the true

proportions of younger and older teens who include false information in their profiles?

Explain your answer.

Short Answer

Expert verified

a. There is 95%assurance that correct proportion of young teens include wrong details in their profile is between 0.120and0.297.

b. There is not enough convincing proof.

Step by step solution

01

Given Information

It is given that for 95%confidence interval for correct difference in proportion of young teens and older teens that have false information in their respective profiles.

02

a. To interpret Confidence Interval

From given data, there is 95%confidence that correct proportion of young teens has included wrong information in profiles lies between 0.120and 0.297high than correct proportion of older teens that has wrong details in their profiles.

03

To Explain the convincing evidence of a difference in the true proportion of younger and older teens of confidence interval

Confidence Interval does not contain zero, it is likely that there is not any difference in correct proportion of young and older teens.

Hence, there is enough of the convincing proof in true proportion of young and old teens that has wrong data in their profile.

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