Question

The compressive strength of concrete is being tested by a civil engineer who tests 12 specimens and obtains the following data: 2215, 2237, 2249, 2204, 2225, 2301, 2281, 2263, 2318, 2255, 2275, 2295 Assuming that the measurements represent a random sample from a normal population, construct a 95% two-sided confidence interval on the mean strength.

Answer 1

To construct a 95% confidence interval for the compressive strength of concrete, compute the sample mean, standard deviation, and standard error, then use the t-distribution to determine the margin of error and apply it to the sample mean.

Step-by-step explanation:

Constructing a 95% Confidence Interval

To construct a 95% confidence interval for the compressive strength of concrete, compute the sample mean, standard deviation, and standard error, then use the t-distribution to determine the margin of error and apply it to the sample mean.

The objective is to calculate a 95% two-sided confidence interval for the mean compressive strength of concrete, based on the sample data provided. Here are the steps to construct the confidence interval:

The calculation requires that the population is normally distributed, which is stated in the question. Once the confidence interval is constructed, it will give the range within which the true mean compressive strength of concrete lies with a 95% confidence level.