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

### Instruction:
 玛蒂尔达买了一部手机，花了300美元。然后她决定不使用它，以255美元的价格卖掉了。她损失了初始成本的百分之多少？


### Response:
 300美元 - 255美元 = 45美元损失
45美元是300美元的百分之多少？(($45/$300)*100)=15%