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ZX-585EE33A612024年12月北美A卷 · 第 4 题
2024年12月北美A卷 · 原库模块 1 · Q4 原库参考解析
A sleep study consisted of 77 participants, of which 69 participants each had an average of more than 120 minutes of rapid eye movement (REM) sleep per night. If a participant from this sleep study is selected at random, what is the probability of selecting a participant that had an average of more than 120 minutes of REM sleep per night?
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