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

### Instruction:
Bill's roof can bear 500 pounds of weight. If 100 leaves fall on his roof every day, and 1000 leaves weighs 1 pound, how many days will it take for his roof to collapse?

### Response:
First figure out how many leaves the roof can hold by multiplying the roof's weight limit in pounds by the exchange rate between leaves and pounds: 500 pounds * 1000 leaves/pound = <<500*1000=500000>>500000 leaves.
Then divide that by the number of leaves that fall each day to find how many days before the roof collapses: 500000 leaves / 100 leaves/day = <<500000/100=5000>>5000 days
#### 5000