1985 AMC 8 Problem 12
Attempt Problem 12 of the 1985 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 1985 AMC 8 solutions, or check the answer key.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
12.
A square and a triangle have equal perimeters. The lengths of the three sides of the triangle are cm, cm, and cm. The area of the square, in square centimeters, is
Answer: B
Small hint:
Add the triangle’s three sides to get the common perimeter
Big hint:
The square’s side is one fourth of its perimeter
Solution:
The triangle’s perimeter is cm, so the square also has perimeter cm.
The square’s side is cm, so its area is
Thus, the correct answer is B .
Problem 12 in other years
- 1986 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
- 1995 AMC 8
- 1996 AMC 8
- 1997 AMC 8
- 1998 AMC 8
- 1999 AMC 8
- 2000 AMC 8
- 2001 AMC 8
- 2002 AMC 8
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