3/7 x 1/6 = 1/14 is the probability of choosing an odd and then the 20

3 ways to get odd out of 7 possibilities. 1 way to get 20 out of 6 remaining tiles.

Multiply the probabilities to get the compound probability.

Or if you wanted 20 and then an odd, it's

1/7 x 3/6 which also = 1/14