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? Let's be accurate as possible.

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
There are 2 * 12 = 24 apartments he needs keys for. So he needs 24 * 3 = 72 keys.
The answer: 72.