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 appropriate hypotheses to determine if the manufacturer's claim appears reasonable are

Question

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 appropriate hypotheses to determine if the manufacturer's claim appears reasonable are
A) H₀: μ = 250 versus H₁: μ ≠ 250.
B) H₀: μ ≥ 250 versus H₁: μ < 250.
C) H₀: μ ≤ 250 versus H₁: μ > 250.
D) H₀: μ ≥ 257.3 versus H₁: μ < 257.3.

Quizplus · Accepted Answer

The null hypothesis (H₀) should reflect the manufacturer's claim that the mean power consumption is no more than 250 W, which translates to μ ≤ 250. The alternative hypothesis (H₁) would then be that the mean power consumption is greater than 250 W, which is μ > 250.

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