In the study of textiles and fabrics, the strength of a fabric is a very important consi...

In the study of textiles and fabrics, the strength of a fabric is a very important consideration. Suppose that a sig nifi cant number of swatches of a certain fabric are subjected to different “loads” or forces applied to the fabric. The data from such an experiment might look as follows:

a. Make a scatterplot of the proportion failing versus the load on the fabric.

b. Using the techniques introduced in this section, calculate for each of the loads and fit the line . What is the significance of a positive slope for this line? c. What proportion of the time would you estimate this fabric would fail if a load of 60 lb/sq in. were applied?

d. In order to avoid a “wardrobe malfunction,” one would like to use fabric that has less than a 5% chance of failing. Suppose that this fabric is our choice for a new shirt. To have less than a 5% chance of failing, what would you estimate to be the maximum “safe” load in lb/sq in.?