Question

1) More time on the Internet: A researcher polled a sample of 1052 adults in the year 2010, asking them how many hours per week they spent on the Internet. The sample mean was 10.19 with a standard deviation of 13.81. A second sample of 2022 adults was taken in the year 2012. For this sample, the mean was 10.87 with a standard deviation of 14.92. Assume these are simple random samples from populations of adults. a) State the null and alternative hypothesis b) What is the significant level? c) Compute the p-value d) Do you reject the null hypothesis? Explain? e) Can you conclude that the mean number of hours per week spent on the Internet increased between 2010 and 2012? Use the = 01 level of significance.

Answer 1

- n =1652 a = 10.19 Si= 13.81 n₂ = 2082 ta 10.87 Se = 16.92 - Claim - mean increased - Mer24 Ho: M,=h Hai Mie Ma a null I alternate Significance level (C) Test statistic a . 10.19 -10.87 (13.81² 14.92² V T052 + 2022 Test Statistic = -196) P-value = P( Z 2-126) = 0.1038 P-value =0.1038 rah cey P-value greater than alpha (0.05) So we fail to reject null hypothesis There is no sufficient evidence to Conclude that mean number of hours - has increased.