There is a cat in each of the 4 corners of the room. Opposite each cat sits 3 more cats. How many cats are there in the room?

Let’s read the condition carefully.
Let’s find how many cats sit in front of the cats in the corners, if there are 4 cats in the corners:
4 * 3 = 12 (pieces)

Let’s find how many cats are sitting in the room if 12 cats are sitting opposite the cats in the corners:
12 + 4 = 16 (pieces)

Answer: There are 16 cats in the room.