1994 AMC 8 Problem 21
Below is the professionally curated solution for Problem 21 of the 1994 AMC 8, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 1994 AMC 8 solutions, or check the answer key.
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Difficulty rating: 980
21.
A gumball machine contains red, white, and blue gumballs. The least number of gumballs a person must buy to be sure of getting four gumballs of the same color is
Solution:
In the worst case, a person could draw red, white, and blue, which is gumballs, without yet having four of any color.
The next (tenth) gumball must match one of these colors, giving four of that color. So gumballs are needed.
Thus, the correct answer is C .
Problem 21 in Other Years
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