Use reasoning to lead to the answer of the following question:
Tim owns rental properties. He decides to replace all the locks and needs to get 3 keys per lock. He owns two apartment complexes which each have 12 apartments. How many keys does he need to make?

72
There are 2 * 12 = 24 apartments he needs keys for.

So he needs 24 * 3 = 72 keys.

.

Final answer: 72