An Engineer Wants to Know If the Average Amount of Energy

question 59

Essay

An engineer wants to know if the average amount of energy used in his factory per day has changed since last year. The factory used an average of 2,000 megawatt hours (mwh) per day prior to last year. Since last year, the engineer surveyed 400 days and found the average energy use was 2,040 mwh per day. Assume that the population standard deviation is 425 mwh per day.
A) Specify the null and alternative hypotheses to determine whether the factory's energy use has changed.
B) Calculate the value of the test statistic and the p-value.
C) At the 5% significance level, can you conclude that the energy usage has changed? Explain.

• A) Specify the null and alternative hypotheses to determine whether the factory's energy use has changed.
• B) Calculate the value of the test statistic and the p-value.
• C) At the 5% significance level, can you conclude that the energy usage has changed? Explain.

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Definitions:

Various Prices

Diverse or differing price points at which goods or services are offered in the market.

Maximum Price

The highest price that can be legally charged for a good or service.

Demand Curve

A graph showing the relationship between the price of a good and the quantity demanded by consumers at those prices.

Hundredth Unit

The hundredth unit refers to the specific position or measure of something that is one hundred in a sequence or collection.