AMC 8 1994 Problem 21

AMC8 1994 年第 21 题

鸽巢原理与策略★★★☆☆

A gumball machine contains 9 red, 7 white, and 8 blue gumballs. The least number of gumballs a person must buy to be sure of getting four gumballs of the same color is

一台口香糖机装有 9 颗红色、7 颗白色和 8 颗蓝色口香糖。要确保得到四颗同色的口香糖，最少需要买多少颗？

A.8
B.9
C.10
D.12
E.18

正确答案 · Correct Answer

解析 · Solution

Solution 1

If a person gets three gumballs of each of the three colors, that is, 9 gumballs, then the

10^{\text{th}}

gumball must be the fourth one for one of the colors. Therefore, the person must buy

\text{(C)10}

gumballs.

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