Chapter 3

Q. 3.15

Comparison of Outdoor Paint

A testing lab wishes to test two experimental brands of outdoor paint to see how long each will last before fading. The testing lab makes 6 gallons of each paint to test. Since different chemical agents are added to each group and only six cans are involved, these two groups constitute two small populations. The results (in months) are shown. Find the mean of each group.

Brand A Brand B
10 35
60 45
50 30
30 35
40 40
20 25


Verified Solution

The mean for brand A is

μ =\frac{ΣX}{N} = \frac{210}{6} = 35\text{ months}

The mean for brand B is

μ =\frac{ΣX}{N} = \frac{210}{6} = 35\text{ months}