Question

In a random sample of 365 adult Internet users aged 18 to 29, 87 had used Twitter. In a separate random sample of 520 adult Internet users aged 30 to 49, 76 had used Twitter. Answer question 18-20 to test the claim that the proportion of younger adult Internet users who had used Twitter(population 1) is larger than the proportion of older adult Internet users who had used Twitter. Use a significance level of 0.01.

Answer 1

Given that,

n1 = 365 and x1 = 87

n2 = 520 and x2 = 76

significance level

The null and alternative hypotheses are,

Test statistic is, Z = 3.48

P-value = P(Z > 3.48) = 0.0003

Since, p-value = 0.0003 < significance level of 0.01

we reject the null hypothesis ( H0 ).

Conclusion : There is sufficient evidence to supoort the claim that the proportion of younger adult Internet users who had used Twitter(population 1) is larger than the proportion of older adult Internet users who had used Twitter.