A sheepdog brings a flock of sheep back to the farm at day's end. "I brought back 30 sheep," the dog tells the farmer. "But I only have 27 sheep," the farmer protests.  "Oh, I know," said the sheepdog. "I rounded them up."

What's So Funny?

The expression "to round up" has two meanings:

1. In mathematics, rounding means going to the next even number.  If the total is 26, 27, 28, or 29, it will be "rounded up" to 30  If the total is 24, 23, 22, or 21, it will be "rounded down" to 20.

2. In herding, like in police work, "rounding up" means gathering together many stray individuals (for example, sheep or cows in ranching, or criminal suspects in policing).