Weighing Pigs

A man decides he wants to have a pig roast, so he goes out to a pig farm to buy one. He agrees on a per pound price with the farmer and then begins to select a pig."How about that one?" "OK, replies the farmer."The farmer then picks up the pig, puts its tail in his mouth, lets it hang from his mouth, and then declares, "This one weighs 74 pounds." "That's amazing," the man says, "are you sure you can tell a pig's weight by using that method?" "Yep," replies the farmer, "we've used this method in our family for generations." To prove his accuracy, the farmer puts the pig on a scale and it weighs exactly 74 pounds."My son can do it too," boasts the farmer. And sure enough, the farmer's son comes over, puts another pig's tail in his mouth, lets it hang, and then says, "This one weighs 83 pounds." The farmer then confirms his son's accuracy with the scale. "My wife can do it too," says the farmer."Son, go get your mother." The boy runs off to the house and returns a few minutes later."Mom can't come out right now," says the son, "she's busy weighing the mailman."