Baby Scale

A Female holding a baby walks into a drug store and asks a clerk if she can use the stores free baby scale.

"Sorry, maam," says the clerk .

"Our baby scale is out for repairs. But we can figure the babys weight if we weigh mother and baby together on the adult scale, and then weigh the mother alone, and subtract the second number from the first."

"Oh, that wont work," says the Female

"Why not ?" asks the clerk.

"Because," says the Female, "Im not the mother -- Im the aunt."

--purushothama