Find the probability of the following event:

Question

tossing a coin heads up or rolling a 3 with a number cube.

I got: 1/2+1/6 = 2/3 but the right answer is 7/12. I don't understand how to get 7/12. Please help.

Answer 1

1/2 + 1/6 = 6/12 + 2/12 = 8/12 = 2/3

Neither do I. Probably a typo in the answer key.