Asked by Jenna Garland on May 02, 2024
Verified
In order to estimate the average electric usage per month, a sample of 64houses was selected and the electric usage was determined.Assume a population standard deviation of 320 kilowatt-hours.At 95% confidence, the size of the margin of error is
A) 1.96.
B) 40.00.
C) 78.40.
D) 65.80.
Margin of error
The amount of error that can be tolerated in survey or poll results, often used in describing the accuracy of a confidence interval.
Electric usage
The amount of electrical energy consumed by a device, household, or establishment over a given time period.
- Utilize appropriate equations to calculate the standard error of the mean and the margin of error in different situations.
Verified Answer
LV
Lucas VenegasMay 03, 2024
Final Answer :
C
Explanation :
We can use the formula for margin of error:
Margin of error = z* (standard deviation / sqrt(sample size))
Where z corresponds to the confidence level, which is 1.96 for 95% confidence level.
Plugging in the values:
Margin of error = 1.96 * (320 / sqrt(64))
Margin of error = 1.96 * 40
Margin of error = 78.40
Therefore, the size of the margin of error is 78.40 kilowatt-hours.
Margin of error = z* (standard deviation / sqrt(sample size))
Where z corresponds to the confidence level, which is 1.96 for 95% confidence level.
Plugging in the values:
Margin of error = 1.96 * (320 / sqrt(64))
Margin of error = 1.96 * 40
Margin of error = 78.40
Therefore, the size of the margin of error is 78.40 kilowatt-hours.
Learning Objectives
- Utilize appropriate equations to calculate the standard error of the mean and the margin of error in different situations.