Below is an instruction that describes a task. Write a response that appropriately completes the request in English. Please answer in English.

### Instruction:
Melissa bought 4 packs of tennis balls for $24 in total. Each pack contains 3 balls per pack. How much did it cost Melissa for each tennis ball?

### Response:
Let x be the cost of one tennis ball.
The total cost of the 4 packs of tennis balls is x*3*4=$24.
So, the cost of one tennis ball is x = (24/12) = $<<(24/12)=2>>2.
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