First of all, the first prize accounts for110 (=1-9/10) of the total number of winners.

The total ratio of the first prize and the second prize is not written, and the guess is 2/5. Generally speaking, the first prize is less than the second prize and the second prize is less than the third prize. If the total number of first and second prizes is 1/5, then both first and second prizes are110, which is unreasonable. If the first and second prizes total 3/5 or 4/5, it is unreasonable that the second prize is more than the third prize. So the reasonable situation is that the first prize and the second prize add up to 2/5. Then the third prize is 3/5 and the second prize is1-113/5 = 3/10, so the number of participants * * * is12/(1.