Hyram Drant a research analyst for the city fire department

Hyram Drant, a research analyst for the city fire department, suspects that old water pumps are more likely to fail. From the data in the accompanying table, construct a contingency table and check Drant’s suspicion. How else could this problem be analyzed? (Hint: The sub-categories of “age of pump” can be “less than 30 years” and “30 years over”; the sub-categories of “pump performance” can be “pump failed” and “pump did not failed” as indicated by the problem. Organize the data and build a contingency table according to these subcategories and then analyze.)

Solution