<human>:  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?
<bot>: How many leaves can the roof hold? ** First, find how many leaves the roof can hold: 500 pounds * 1000 leaves/pound = <<500*1000=500000>>500000 leaves
How many days will it take for the roof to collapse? ** 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