Twenty-two fourth-grade children were randomly divided into two groups. Group A was taught spelling by a phonetic method. Group B was taught spelling by a memorization method. At the end of the fourth grade, all children were given a standard spelling exam.

The scores are as follows.

Use a 1% level of signifi­cance to test the claim that there is no difference in the test score distributions based on instruction method.

(a) What is the level of signifi­cance? State the null and alternate hypotheses.

(b) Compute the sample test statistic. What is the sampling distribution?

What conditions are necessary to use this distribution?

(c) Find the P-value of the sample test statistic.

(d) Conclude the test.

(e) Interpret the conclusion in the context of the application.

Group A77 95 83 69 85 92 61 79 87 93 65 78 Group B62 90 70 81 63 75 80 72 82 94 65 79