问题
单项选择题
Three stacks containing equal numbers of chips are to be made from 9 red chips, 7 blue chips，and 5 green chips．If all of these chips are used and each stack contains at least 1 chip of each color, what is the maximum number of red chips in any one stack ？（）
A．7
B．6
C．5
D．4
E．3
答案
参考答案：C
解析：
因为筹码的总数为9+7+5=21，所以每堆中有7个筹码；又因为每堆中至少有每种颜色的一个筹码，所以在任一堆中红色筹码最多为5个，蓝色筹码最多为5个，绿色筹码最多为3个。