A farmer comes home to find his sheepdog waiting for him.
The sheepdog says:
“I herded the sheep into the barn, just like you asked!”
“You sure you got them all?” The farmer replies.
“Yep! All 40 of them!” Says the sheepdog.
“40? But I only have 37 sheep.” Replies the farmer.
The sheepdog answers:
“I know. I rounded them up for you.”