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

### Instruction:
 约翰晚餐吃了一袋薯片，然后晚餐后吃了两倍的数量。他吃了多少袋薯片？


### Response:
 他晚餐后吃了2 * 1 = <<2*1=2>>2袋薯片
所以他一共吃了2 + 1 = <<2+1=3>>3袋薯片