# I need the correct answer for ch. 7

**Question description**

**Problem #38 Electricity Consumption:**

The U.S. Energy Information Association claims that the mean monthly residential electricity consumption in your town is more than 874 kilowatt-hours (kWh). You want to test this claim. You find that a random sample of 64 residential customers has a mean monthly electricity consumption of 905 kWh. Assume the population standard deviation is 125 kWh. At α = 0.05, do you have enough evidence to support the association's claim? *(Adapted from U.S. Energy Information Association)*

- Identify the claim and state H
_{o}and H_{a} - Find the critical value(s) and identify the rejection region(s)
- Find the standardized test statistic z
- Decide whether to reject or fail to reject the null hypothesis, and
- Interpret the decision in the context of the original claim.

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