Dante's Infernal Puzzle Collection -- 14. Pianto

(The book's answer is wrong again. Let me explain why later.)

The answer is that we need more information.

Suppose there were originally 200 women and 100 men. Then the number of women in the pit would be 200 * .42 = 84, whereas the number of men would be 100 * .28 = 28. The male-to-female ratio is 28:84, or 1:3.

Now suppose there were initially 100 women and 200 men. The number of women in the pit is 100 * .42 = 42, and the number of men in the pit is 200 * .28 = 56. The male-to-female ratio is 56:42, which is equivalent to 4:3.

The point is, the answer completely depends on the initial number of men and women. Without this information,  we cannot provide an answer to the question.

The book's solution gives an extremely simplistic answer by simply taking the ratio of 28 to 42. This is incorrect.