1998 AMC 8 Problem 20
Attempt Problem 20 of the 1998 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 1998 AMC 8 solutions, or check the answer key.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
20.
Let be a square piece of paper. is folded onto and then is folded onto The area of the resulting figure is square inches. Find the perimeter of square
Answer: D
Small hint:
After the two folds, four congruent pieces make the original square.
Big hint:
Use the resulting area to find the original side length.
Solution:
After the two folds, the resulting triangle has area Four congruent copies of this triangle make the original square.
So the square has area giving side length Its perimeter is
Thus, the correct answer is D .
Problem 20 in other years
- 1985 AMC 8
- 1986 AMC 8
- 1987 AMC 8
- 1988 AMC 8
- 1989 AMC 8
- 1990 AMC 8
- 1991 AMC 8
- 1992 AMC 8
- 1993 AMC 8
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