set X has 5 numbers, and the average is greater than medium; set Y has 7 numbers, and the average is greater than medium. set Z combined x and y, is the average greater than medium?
(1) medium of set X is greater than medium of set Y (2)average of set X is greater than average of set Y
题目意思都懂，就是应该从哪里入手呢？思路？
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