Question: 59: The manufacturing company in Problem 3.58 also produces electric insulators. If the insulators break when in use, a short circuit is likely to occur. To test the strength of the insulators, destructive testing is carried out to determine how much force is required to break the insulators. Force is measured by observing how many pounds must be applied to the insulator before it breaks. The data from 30 insulators from this experiment are contained in the file

force.xls

1,870 1,728 1,656 1,610 1,634 1,784 1,522 1,696 1,592 1,662

1,866 1,764 1,734 1,662 1,734 1,774 1,550 1,756 1,762 1,866

1,820 1,744 1,788 1,688 1,810 1,752 1,680 1,810 1,652 1,736

a. Calculate the mean, median, range, and standard deviation for the force variable.

b. Interpret the measures of central tendency and variability in (a).

c. Construct a box-and-whisker plot and describe its shape.

d. What can you conclude about the strength of the insulators if the company requires a force measurement of at least 1,500 pounds before breakage?