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

### Instruction:
Bobby wanted pancakes for breakfast.  The recipe on the box makes 21 pancakes.  While he ate 5 pancakes, his dog jumped up and was able to eat 7 before being caught.  How many pancakes does Bobby have left?

### Response:
 บ็อบบี้ทำแพนเค้กได้ 21 แผ่น เขาทานไป 5 แผ่นและสุนัขของเขากินไป 7 แผ่นดังนั้น 21-5-7 = <<21-5-7=9>>9 แผ่นเหลืออยู่