TABLE 9-3
An appliance manufacturer claims to have developed a compact microwave oven that consumes a mean of no more than 250 W. From previous studies, it is believed that power consumption for microwave ovens is normally distributed with a population standard deviation of 15 W. A consumer group has decided to try to discover if the claim appears true. They take a sample of 20 microwave ovens and find that they consume a mean of 257.3 W.
-Referring to Table 9-3, the population of interest is
A) the power consumption in the 20 microwave ovens.
B) the power consumption in all such microwave ovens.
C) the mean power consumption in the 20 microwave ovens.
D) the mean power consumption in all such microwave ovens.

Question

Quizplus · Accepted Answer

The population of interest in this scenario is not just the sample of 20 microwave ovens, but rather all microwave ovens. The consumer group wants to determine if the manufacturer's claim is true for all such microwave ovens, not just the ones they sampled. Therefore, the population of interest is the power consumption in all such microwave ovens, making choice B the best answer.

TABLE 9-3 An Appliance Manufacturer Claims to Have Developed a Compact Microwave