Final answer:
To estimate the true mean price for the graphing calculator with 95% confidence, calculate the sample mean and margin of error. The 95% confidence interval for the true mean price is $129.06 to $147.44.
Step-by-step explanation:
To estimate the true mean price for the graphing calculator with 95% confidence, we can calculate the sample mean and the margin of error.
The sample mean is the average of the prices, which is the sum of the prices divided by the number of prices. The margin of error is a range within which the true mean is likely to fall. To calculate the margin of error, we use the formula:
Margin of Error = Critical Value * (Sample Standard Deviation / Square Root of Sample Size)
Using the given prices, the sample mean is $138.25. The critical value for a 95% confidence level is approximately 1.96. The sample standard deviation is $10.48 and the sample size is 8. Plugging these values into the formula, we can calculate the margin of error to be approximately $9.19.
Therefore, the 95% confidence interval for the true mean price of the graphing calculator is $138.25 ± $9.19, which is approximately $129.06 to $147.44.