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

### Instruction:
 Nate正在读一本400页的书。他已经读完了书的20%。他还需要读多少页才能读完整本书？


### Response:
 他已经读了400 x 20/100 = <<400*20/100=80>>80页。
因此，他还需要读400 - 80 = <<400-80=320>>320页才能读完整本书。