AMC 8 1991 Problem 11
AMC8 1991 年第 11 题
排列与组合★★★☆☆
Problem There are several sets of three different numbers whose sum is 15 which can be chosen from . How many of these sets contain a 5?
从 中可以选出几组三个不同数的集合，其和为 15？这些集合中有多少个包含 5？
- A.3
- B.4
- C.5
- D.6
- E.7
正确答案 · Correct Answer
B
解析 · Solution
解析整理中
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