ONE QUESTION, ONE STEP
ZX-074DE708AFPSAT 8/9 P2 · 第 21 题
PSAT 8/9 P2 · 原库模块 3 · Q21 原库参考解析
After 20% of the original number of marbles in a group were removed from the group, 360 marbles remained in the group. How many marbles were removed from the group?
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解题思路
容易忽略的一步
