A random sample of 30 households was selected as part of a study on electricity usage, and the number of kilowatt-hours (kWh) was recorded for each household in the sample for the March quarter of 2016. The average usage was found to be 375kWh and the standard deviation of the usage was 81kWh. Suppose if usage is above 390kWh, this will trigger a rate increase for the next quarter billing. Give the information, you should Accept the null hypothesis Reject the null hypothesis and don't raise rates Fail to reject the null hypothesis and don't raise rates Reject the null hypothesis and raise rates Fail to reject the null hypothesis and raise rates
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Null hypothesis (H0): The average electricity usage for households in the March quarter of 2016 is not significantly different from 390kWh. Alternative hypothesis (Ha): The average electricity usage for households in the March quarter of 2016 is significantly Show more…
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