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Chapter 10: Q.2.1 (page 611)

Are teens or adults more likely to go online daily? The Pew Internet and American Life Project asked a random sample of 800 teens and a separate random sample of 2253 adults how often they use the Internet. In these two surveys, 63% of teens and 68%of adults said that they go online every day. Construct and interpret a 90% confidence interval for p1-p2?

Short Answer

Expert verified

The mean and standard deviations are 10 and 0.205 respectively.

Step by step solution

01

Given Information

Sample mean x¯1=27.

Sample mean x¯2=17.

Standard deviation σ1=0.8.

Standard deviation σ2=0.5.

02

Explanation

The formulas to compute the mean and standard deviation are:

μ1-2=μ1-μ2

σ1-2=σ12+n1σ22n2

The mean and standard deviation could be computed as:

μ1-2=μ1-μ2

=27-17

=10

σ1-2=σ12+n1σ22n2

=0.8225+0.5220

=0.205

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