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

question 89

Short Answer

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, for a test with a level of significance of 0.05, the critical value would be ________.

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Definitions:

Frequencies

The number of times a particular data point appears in a set of data.

Nominal Variable

A variable used in statistics to label or categorize without a natural order or ranking.

Interval

A range of values between two points, often used in mathematics and statistics to denote a specific span of numbers.

Time-series Data

Data that consists of sequence of values or events obtained over successive times, often analyzed to understand trends, cycles, or predictions.