Problem:
The table to the right displays the grade distribution of the students in a mathematics class on the last two tests. For example, exactly one student received a '' on Test and a '' on Test (see circled entry). What percent of the students received the same grade on both tests?
Answer Choices:
A.
B.
C.
D.
E.
Solution:
A student received the same grade on both tests if s/he is counted on the main diagonal (from the top left to the bottom right) of the table. Thus the number of students receiving the same grade on both tests is . Consequently of the students received the same grade on both tests.
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions