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

### Instruction:
John Smith buys 3 cakes for $12 each and splits the cost with his brother.  How much did he pay?

### Response:
 เค้กราคา 3*12=$<<3*12=36>>36
ดังนั้นเขาจ่าย 36/2=$<<36/2=18>>18