Counting sheep

Why makes this Joke funny?

The humor in this joke lies in the play on words involving "rounding up," which has a double meaning:

1. Mathematical Rounding Up: In mathematics, "rounding up" refers to increasing a number to the nearest whole number. In this context, it implies that the sheepdog has increased the count of sheep from 17 to 20 as part of a mathematical rounding process.
2. Herding Sheep: "Rounding up" is also a term used in farming, particularly with sheep or cattle, meaning to gather them together from various places. This is a typical task for a sheepdog, who is trained to gather and control sheep.

The humor emerges because the sheepdog takes the farmer`s instruction to "round up" the sheep literally in a mathematical sense, rather than in the usual herding sense. The joke plays on the ambiguity of the phrase "round them up," leading to a humorous misunderstanding between the farmer and the sheepdog. The punchline is unexpected, as the listener initially assumes the sheepdog is referring to herding the sheep, not mathematically adjusting their number.