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In a poll, 53% of internet users aged 18-29 said they use Instagram. It is claimed that a majority of Internet users, aged 18-29, use Instagram

a.

It is claimed that the majority of Internet users use Instagram.

Corresponding to the given claim, the following hypotheses are set up:

Null Hypothesis: The proportion of internet users aged 18-29 who use Instagram is equal to 0.5.

\({H_0}:p = 0.5\)

Alternative hypothesis: The proportion of internet users aged 18-29 who use Instagram is greater than 0.5.

\({H_1}:p > 0.5\)

Here, the sample size (n) is equal to 532.

The sample proportion of Internet users aged 18-29 who use Instagram is given to be equal to:

\(\begin{array}{c}\hat p = 53\% \\ = \frac{{53}}{{100}}\\ = 0.53\end{array}\)

The population proportion of Internet users aged 18-29 who use Instagram is equal to 0.5.

b.

The value of the test statistic is computed below:

\(\begin{array}{c}z = \frac{{\hat p - p}}{{\sqrt {\frac{{pq}}{n}} }}\\ = \frac{{0.53 - 0.5}}{{\sqrt {\frac{{0.5\left( {1 - 0.5} \right)}}{{532}}} }}\\ = 1.384\end{array}\)

Thus, z=1.384.

c.

It is given that the p-value for the test statistic value of 1.384 is equal to 0.0827.

Since the p-value is equal to 0.0827, which is greater than 0.05, the null hypothesis is rejected.

d.

There is not enough evidence to support the claim that the proportion of Internet users aged 18-29who use Instagram is more than 50%.