Math 305 - Hypothesis Testing Questions
Mean Verification
The security department of a factory wants to know whether the true average time required
by the night guard to walk his round is 30 minutes. If, in a random
sample of 32 rounds, the night guard averaged 30.8 minutes with a standard deviation
of 1.5 minutes, determine whether this is sufficient evidence to
reject the null hypothesis μ = 30 minutes in favor of the alternative hypothesis
μ != 30 minutes. Use a p-value of 0.05.
Difference in Means
To compare two kinds of bumpers, six of each kind were mounted on a certain make of compact
car. Then each car was run into a concrete wall at 5 miles per hour, and the following are the costs
of the repairs (in dollars):
| Bumper 1 |
127 |
168 |
143 |
165 |
122 |
139 |
| Bumper 2 |
154 |
135 |
132 |
171 |
153 |
149 |
Use a p-value of 0.01 to test whether there is a significant difference between these two samples.
Difference in Multiple Means
The following are the numbers of mistakes made in five successive weeks by four technicians
working for a medical laboratory.
| Tech 1 |
13 |
16 |
12 |
14 |
15 |
| Tech 2 |
14 |
16 |
11 |
19 |
15 |
| Tech 3 |
13 |
18 |
16 |
14 |
18 |
| Tech 4 |
18 |
10 |
14 |
15 |
12 |
Test at the 0.05 level of significance whether the differences among the four sample
means can be attributed to chance.
You can make use of the
Z Table, T Table, and
F Table.