Question

A piece of copper weighed 4⁄5 of a kilogram and a piece of nickel weighed 3⁄5 of a kilogram. How much more did the piece of copper weigh?

Answer 1

You find the difference in weight by subtacting the weight of the nickel from the weight of the copper.

... (4/5 kg) - (3/5 kg) = (4 -3)/5 kg = 1/5 kg

The piece of copper weighed 1/5 kg more than the piece of nickel.