Fraction of the cost

Yesterday at dinnertime the Man was teaching his son fractions through the medium of strawberries.

Man: There are four strawberries in the bowl. If I take away half of them, how many are left? But if I only take away a quarter of them...?

OK. Now, what's a quarter plus a quarter?

Boy (joyfully): Fifty cents!

That's my Boy - always right on the money.