Question

In a survey, 20 people were asked how much they spent on their child's last birthday gift. The results were roughly bell-shaped with a mean of

2. Estimate how much a typical parent would spend on their child's birthday gift (use a 95% confidence level).

Answer 1

To estimate how much a typical parent would spend on their child's birthday gift, we can use the mean and a 95% confidence level. Given that the mean is 2, we can calculate the margin of error using the standard deviation. Finally, we can use the margin of error to calculate the confidence interval.

Step-by-step explanation:

To estimate how much a typical parent would spend on their child's birthday gift, we can use the mean and a 95% confidence level. Since the results were roughly bell-shaped, we can assume a normal distribution. Given that the mean is 2, we can use the standard deviation to determine the margin of error.

To calculate the margin of error, we need to find the critical value associated with a 95% confidence level. For a normal distribution, this value is approximately 1.96.

The margin of error is calculated by multiplying the critical value by the standard deviation: Margin of error = 1.96 * standard deviation.

Once we have the margin of error, we can calculate the confidence interval. The lower bound of the interval is the mean minus the margin of error, and the upper bound is the mean plus the margin of error. In this case, the confidence interval would be (2 - margin of error, 2 + margin of error).