One tap, working alone at its maximum constant rate, can fill a certain sink in 287 seconds

题目

One tap, working alone at its maximum constant rate, can fill a certain sink in 287 seconds. A second tap, working alone at its maximum constant rate, can fill the same sink in 283 seconds. If both taps work together at their respective maximum constant rates, the time it will take to fill the sink is closest to

选项

142 seconds

150 seconds

177 seconds

200 seconds

270 seconds

解析

注意：如果**一个水龙头**注满水槽需要287秒，那么**两个这样的水龙头**注满水槽所需时间将减半。换句话说，两个287秒的水龙头注满水槽需要143.5秒。因此，如果我们将其中一个287秒的水龙头替换为一个**稍快一些**（283秒）的水龙头，注满水槽的时间将**少于**143.5秒。由于只有一个选项的数值小于143.5秒，所以正确答案一定是A。

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