There are four equal weights on one side of the scale and an apple on the other side.

What can you say that is true about the apple and the weights?

If the apple weighs 12 ounces, how heavy must one weight be?

If the apple weighed 15 ounces, how heavy would one weight be?

If the apple weighed a full pound and the weights were each 4 ounces, what would the scale look like? How do you know? Can you prove it?