Final answer:
A 95% confidence interval estimate of the mean can be constructed using the formula CI = (sample mean) ± (critical value * standard deviation / sqrt(sample size)). The practical use of confidence interval is to estimate the true population mean based on a sample, providing a range of values within which we are confident the true mean lies.
Step-by-step explanation:
A 95% confidence interval for the mean can be constructed using the formula:
CI = (sample mean) ± (critical value * standard deviation / sqrt(sample size))
In this case, the sample mean is 41 and the critical value for a 95% confidence interval is 1.96 (assuming a large sample size). The standard deviation and sample size are not provided, so we cannot calculate the exact confidence interval. However, we can provide an example of how to calculate it once those values are given.
The practical use of a confidence interval is to estimate the true population mean based on a sample. It provides a range of values within which we are confident the true mean lies. This can be useful in making decisions or drawing conclusions based on limited data.