478 Chapter 10:Analysis of Variance
Machine
123
Detergent 1 53 50 59
Detergent 2 54 54 60
Detergent 3 56 58 62
Detergent 4 50 45 57(c) Test the hypothesis that the detergent used does not affect the score.
(d) Test the hypothesis that the machine used does not affect the score.
Use, in both (c) and (d), the 5 percent level of significance.
23.An experiment was devised to test the effects of running 3 different types of gasoline
with 3 possible types of additive. The experiment called for 9 identical motors to
be run with 5 gallons for each of the pairs of gasoline and additives. The following
data resulted.
Mileage Obtained
Additive
Gasoline 1 2 3
1 124.1 131.5 127
2 126.4 130.6 128.4
3 127.2 132.7 125.6(a) Test the hypothesis that the gasoline used does not affect the mileage.
(b) Test the hypothesis that the additives are equivalent.
(c) What assumptions are you making?
24.Suppose in Problem 6 that the 10 people placed on each diet consisted of 5 men
and 5 women, with the following data.Diet 1 Diet 2
Women 7.6 19.5
8.8 17.6
12.5 16.8
16.1 13.7
18.6 21.5
Men 22.2 30.1
23.4 24.2
24.2 9.5
32.2 14.6
9.4 11.2