Question

Everyâ week, Ben plays the piano for four hoursâ, and his grade on each psych test is 80 percent. Lastâ week, after playing for four hoursâ, Ben considered playing for an additional hour. He decided to play for another hour and cut his study time by oneâ hour, but last week his psych grade was 65 percent.

Did Mary make her decision on the margin?

a. Mary's decision was not made at the margin because she could have chosen not to play the piano but didn't
b. Mary's decision was not made at the margin because the marginal cost of a lower grade always exceeds its marginal benefits
c. Mary's decision was made at the marginal because her grade fell by only 20 percentage points
d. Mary's made her decision at the marginal because the considered the benefit and cost of one additional hour of playing the piano
e. Mary's decision was not made at the marginal because she didn't compare the total benefit and total cost of a third hour of playing the piano

Answer 1

Answer: d. Mary's made her decision at the marginal because the considered the benefit and cost of one additional hour of playing the piano.

Explanation: Making marginal decisions or making decision on the margin involves making comparison between the cost and benefit attached to a particular behavior or involvement before making a decision. In the scenario above, the additional benefit attached to playing one more hour of piano and the cost incyrred by cutting reading hour by one hour was weighed and considered by Ben before finally making a decision. This means the decision was made on the margin.