2015 AMC 8 Problem 19
Attempt Problem 19 of the 2015 AMC 8 below, then check your answer against the video solution and professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2015 AMC 8 solutions, or check the answer key.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
19.
A triangle with vertices at and is plotted on a grid. What fraction of the grid is covered by the triangle?
Answer: A
Small hint:
Put the triangle inside a small rectangle aligned to the grid.
Big hint:
Subtract the three corner right triangles from the rectangle.
Video solution:
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Written solution:
The total area of the grid is To find the area of the triangle, place it inside the -by- rectangle shown below.
The rectangle has area The three corner triangles have areas and Therefore,
Therefore, the fraction of the area is
Thus, the correct answer is A .
Problem 19 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
- 1994 AMC 8
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- 1998 AMC 8
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