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

### Instruction:
Julia bought 3 packs of red balls, 10 packs of yellow balls, and 8 packs of green balls. There were 19 balls in each package. How many balls did Julie buy in all?

### Response:
 จำนวนแพ็คทั้งหมดคือ 3 + 10 + 8 = <<3+10+8=21>>21 แพ็ค
จูลีย์ซื้อลูกบอลในแต่ละแพ็ค 19 ลูก ดังนั้นเธอซื้อลูกบอลทั้งหมด 21 × 19 = <<21*19=399>>399 ลูก