Question

For all of these questions don't use the p value method instead use the "5 steps of hypothesis testing." Or I will get all of these wrong and I really need the help!!

8) Adults in different age groups were given a reading test and the scores were the same for 19-24 year olds and 40-49 year olds. A random sample of scores from a later year showed the following results. At α (alpha) = 0.10 is there evidence to support the claim that the scores of the older group are higher? 19-24 Group, Mean score 280, σ=56.2, sample size 40 40-49 Group, Mean score 320, σ=53.1, sample size 35

Answer 1

The test statistic is

At = 0.10, the critical value is -z_0.1 = -1.28

Since the test statistic value is less than the critical value (-3.17 < -1.28), so we should reject the null hypothesis.

At 0.10 significance level, there is sufficient evidence to support the claim that the scores of the older group are higher.