Ten Problems

In one jar, put one white token. In the other jar, put the remaining 49 white tokens and 50 black tokens.

Solution

Solution

If the Pilkins staff had been 11 in number, and the Radson staff 12, they could have sat down differently in 165 and 495 ways respectively, which would have solved the question. Only we were told that there happened to be the same number of men in each staff. Therefore the answer is 15 in threes for 455 days, and 15 in fours for 1365 days.

Source: 536 Puzzles and Curious Problems by Dudeney

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