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

### Instruction:
 如果10个人用10天的时间铲掉10,000磅的煤炭，那么半数的这10个人需要多少天才能铲掉40,000磅的煤炭？


### Response:
 每天每人铲掉10000/10/10=<<10000/10/10=100>>100磅的煤炭。
每天每人铲掉8000磅的煤炭，所以需要8000/100=<<8000/100=80>>80天。