Question

In a bag of keys, there are 12 silver keys, 5 black keys, 11 copper keys, and 2 painted keys of various colors. One key is drawn out at random. What is the probability that the key that is drawn is silver or copper?

Answer 1

The total number of keys equals:
12 + 5 + 11 + 2 = 30 keys

The probability to pick a sliver key is:
12/30 = 2/5

The probability to pick a copper key is:
11/30

Hope that helps