A tractor manufacturing plant has been experiencing problems with the division that makes the transmissions. A Pareto diagram, shown in Figure 18.5.1, has been constructed based on recent experience.
a. What is the most important problem, in terms of the number of transmissions affected? What percent of all difficulties does this problem represent?
b. What is the next most important problem? What percent does it represent?
c. What percent of defective transmissions do the top two problems, taken together, represent?
d. What percent of problems do the top three problems together represent?
e. Write a paragraph, as if to your supervisor, summarizing the situation and recommending action.
FIGURE 18.5.1

700 600 500 400 300 e 200 100 100% 87.7% 79.9% 67.6% 0.0% Broken Rubber Clogged Not Needed Wrong Broken gear washer tube enough ajust fer shaft broken oil ment TABLE 18.5.1 Frequency of Occurrence of Various Problems in Candy Manufacturing Cause of Problem Miscellaneous Not enough coating Squa shed Too much coating Two stuck together Number of Cases 526 292 89 57