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

### Instruction:
The tripodasaurus has three legs. In a flock of tripodasauruses, there is a total of 20 heads and legs. How many tripodasauruses are in the flock?

### Response:
 สัตว์แต่ละตัวมีทั้งหมด 1+3=<<1+3=4>>4 หัวและขา
ดังนั้น มีไตรโพดาซอรัสในฝูง 20/4=<<20/4=5>>5 ตัว