A farmer had 297 cows. When he rounded them up, he found he had 300.

Behind the Groan

Farm Work Meets Rounding

On a farm, rounding up cows means gathering the herd into one place. In arithmetic, rounding 297 to the nearest hundred produces 300. The joke lets the practical farm meaning lead, then quietly swaps in the mathematical result. Say “297” clearly so listeners keep the exact number in mind. A small pause after “rounded them up” gives the familiar ranching phrase time to register before the new total reveals the second meaning. It is especially useful when a math lesson needs a quick, clean example.