Samples were drawn from four populations. The sample sizes were n1 = 9, n2 = 7, n3 = 10, n4 = 8.

The sample means were

̄x1 = 73.5, ̄x2 = 74.8, ̄x3 = 75.1, ̄x4 = 78.2. The sample standard deviations were s1 = 2.5, s2 = 4.5, s3 = 3.8, s4 = 3.2. The grand mean was x̄̄ = 75.34.

a. Compute the sums of squares SSTr and SSE.

b. How many degrees of freedom are there for SSTr and SSE?

c. Compute the mean squares MSTr and MSE.

d. Compute the value of the test statistic F.

e. Can you conclude that two or more of the population means are different? Use the α = 0.05 level of significance.