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

### Instruction:
Mary wants to bake 10 apple pies for a charity event. Each pie needs 8 apples and she already harvested 50 apples from the trees in her garden. How many more apples does she need to buy to make all 10 pies?

### Response:
 แต่ละพายต้องใช้แอปเปิ้ล 8 ลูก
ดังนั้น 10 พายต้องใช้ 10*8=<<10*8=80>>80 ลูก
เธอมีแอปเปิ้ล 50 ลูก
ดังนั้นเธอต้องซื้อเพิ่มอีก 80-50=<<80-50=30>>30 ลูก