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

### Instruction:
 莉迪亚有一本书的收藏。她的收藏比她的朋友苏珊的收藏多四倍。苏珊和莉迪亚总共有3000本书。苏珊有多少本书？


### Response:
 让x表示苏珊收藏的书的数量
莉迪亚的收藏有4*x
x+4*x=3000
5*x=3000
x=<<600=600>>600