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

### Instruction:
 朱莉买了3包红球，10包黄球和8包绿球。每包有19个球。朱莉一共买了多少个球？


### Response:
 朱莉买了3 + 10 + 8 = <<3+10+8=21>>21包球。
所以她一共买了21 × 19 = <<21*19=399>>399个球。