Suppose that the owner of an older model Porsche Carrera notices that it takes 7 percent longer for her car to accelerate from zero to sixty than it did when the car was new. From a book relating to relevant parameters, she calculates that 2 percent of the reduction can be attributed to the fact that the car now has larger tires. Also, the alcohol content of the gas accounts for 2 percent, dirty spark plugs for 1 percent, and the fact that she now lives in Los Angeles, where the air is thicker than it was in Denver, where she bought the car, accounts for 1 percent. The owner attributes the remaining 1 percent to general aging of the engine. What method did the owner use in drawing this conclusion?
A) The joint method of agreement and difference.
B) The method of agreement.
C) The method of difference.
D) The method of concomitant variation.
E) The method of residues.

Question

Quizplus · Accepted Answer

The owner used the method of residues, subtracting known causes for the reduction in acceleration (larger tires, alcohol content of gas, dirty spark plugs, and air thickness) from the total reduction to attribute the remaining unexplained portion to general aging of the engine.

Suppose That the Owner of an Older Model Porsche Carrera