There are 15 cards, numbered 1 through 15. If you pick a card, what is the probability that you choo

There are 15 cards, numbered 1 through 15. If you pick a card, what is the probability that you choose an odd number or a two?

We want the P(odd) or P(2).

P(odd) = 1, 3, 5, 7, 9, 11, 13, 15 = 8/15
P(2) = 1/15

Add them both:
8/15 + 1/15 = 9/15

Simplified, we get 3/5.