1998 AMC 8 Problem 23
Attempt Problem 23 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).
23.
If the pattern in the diagram continues, what fraction of the interior would be shaded in the eighth triangle?
Answer: C
Small hint:
At step there are small triangles.
Big hint:
The shaded count is
Solution:
The th triangle has small triangles.
The number of shaded small triangles is
For the shaded fraction is
Thus, the correct answer is C .
Problem 23 in other years
- 1985 AMC 8
- 1986 AMC 8
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