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

### Instruction:
John buys dinner plates and silverware.  The silverware cost $20.  The dinner plates cost 50% as much as the silverware.  How much did he pay for everything?

### Response:
 จานอาหารมีราคา $20 * 0.5 = $<<20*0.5=10>>10 ค่ะ
ดังนั้น เขาจ่ายเงิน $10 + $20 = $<<10+20=30>>30 ค่ะ