1986 AMC 8 Problem 12
Attempt Problem 12 of the 1986 AMC 8 below, then check your answer against the professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 1986 AMC 8 solutions, or check the answer key.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
12.
The table shown displays the grade distribution of the students in a mathematics class on the last two tests. For example, exactly one student received a ‘D’ on Test and a ‘C’ on Test (the circled entry). What percent of the students received the same grade on both tests?
Answer: D
Small hint:
A student with the same grade on both tests lies on the diagonal running from the top-left to the bottom-right of the table
Big hint:
Add the diagonal entries, then divide by and convert to a percent
Solution:
A student received the same grade on both tests exactly when counted on the main diagonal. Those entries are
So the fraction is
Thus, the correct answer is D .
Problem 12 in other years
- 1985 AMC 8
- 1987 AMC 8
- 1988 AMC 8
- 1989 AMC 8
- 1990 AMC 8
- 1991 AMC 8
- 1992 AMC 8
- 1993 AMC 8
- 1994 AMC 8
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