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Seventh grade math interest group
(1) only touches it once, and if it is odd, it will win the prize, so the probability of Xiao Ming winning the prize is 23; ? 1 2 3 1 ( 1, 1) (2, 1) (3, 1) 2 ( 1,2) (2,2) (3,2)

Then p (Xiao Mingsheng) = 49;

(2) To sum up, let Xiao Ming touch n times, all of which are odd numbers, so the probability of Xiao Ming winning the prize is (23) n;

(3) Draw the following tree diagram:

There are 27 equal possibilities, 8 of which are odd.

Then p = 827.

So the answer is: (1) 23; 49; (2)(23)n; (3)827.