Chapter 8, Problem 8.23AC

A manufacturing company produces electric insulators. You define the variable of interest as the strength of the insulators. If the insulators break when in use, a short circuit is likely. To test the strength of the insulators, you carry out destructive testing to determine how much force is required to break the insulators. You measure force by observing how many pounds are applied to the insulator before it breaks. You collect the force data for 30 insulators selected for the experiment and find out that the mean force is 1670.  Based on that, you construct an interval from 1570 to 1770 and claim that this interval can be one of the 95% intervals around the sample means that contain the population mean force.  This interval is   Check all that apply.     a statistic     a parameter     an interval estimate     a point estimate     a confidence interval

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The distance that a spring will stretch varies directly as the force applied to the spring. A force of 15 pounds is needed to stretch a spring 6 inches. What force is required to stretch the spring 8 inches? The required force to stretch the spring 8 inches is (Simplify your answer.) pounds. inches. Enter your answer in the answer box and then click Check Answer. Clear All All parts showing e Type here to search DELL