无聊考据了一下，那个智商题的中文版出处都是（美）M・克莱因《数学与知识的探求》 刘志勇 译 （pdf扫描版下载）这本书

找到了英文原版 Mathematics and the Search for Knowledge by Morris Kline（pdf下载）

Another example of where intuition fails involves a young man who has a choice between two jobs. Each offers a starting salary of $ 1800 per year, but the first one would lead to an annual raise at the rate of $200, whereas the second would lead to a semiannual raise at the rate of $50. Which job is preferable? One would think that the answer is obvious. A raise of $200 per year seems better than one that apparently would amount to only $100 per year. But let us do a little
arithmetic and consider what each job offers during successive six month periods. The first job will pay 900, 900, 1000, 1000, 1100, 1100, 1200, 1200. . . . The second job, which provides a semiannual increase of $50, will pay 900, 950, 1000, 1050, 1100, 1150, 1200, 1250. . . .
It is clear from a comparison of these two sets of salaries that the second job brings a better return during the second half of each year and does as well as the first job during the first half. The second job is the better one. With the arithmetic before us it is possible to see more readily why the second job is better. The semiannual increase of $50
means that the salary will be higher at the rate of $50 for six months or at the rate of $100 for the year, because the recipient will get $50 more for each of the six-month periods. Hence two such increases per year amount to an increase at the rate of $200 per year. Thus far the two jobs seem to be equally good. However, on the second job the
increases start after the first six months, whereas on the first job they do not start until after one year has elapsed. Hence the second job will pay more during the latter six months of each year.

英文版的这个例子倒是使我deja vu了。我觉得我在什么地方见到过，但是印象非常不深。而且远远不如中文版的猥琐和震惊。。。。。

翻了下这本书，原来这作者还举n个类似的“智商题”的例子。。。比如这个

挺有意思的。

这个（美）M・克莱因可能大家不熟悉，但是《数学：确定性的丧失》这本书可可就如雷贯耳了。Mathematics: The Loss of Certainty一书的作者也正是Morris Kline。膜拜之 orz。。。。。