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ZX-8CC8C98AD72026年3月国际A卷 · 第 12 题
2026年3月国际A卷 · 原库模块 3 · Q12 原库参考解析
A research manager selected 2 random samples of ovens of a certain type to estimate the average amount of time this type of oven takes to preheat to 350 degrees Fahrenheit \( (^{∘}F) \) . The research manager recorded the amount of time, in minutes, each oven takes to preheat to \( 350^{∘}F \). Based on the first sample, the research manager estimated that this type of oven takes an average of 14.2 minutes to preheat to \( 350^{∘}F \), with an associated margin of error of 1 minute. Based on the second sample, the research manager estimated that this type of oven takes an average of 14.4 minutes to preheat to , with an associated margin of error of 2.2 minutes. Assuming the margins of error were calculated the same way, which of the following best explains why the first sample obtained a smaller margin of error than the second sample?
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