Adding and subtracting fractions

Put fractions side by side on bars, then add and subtract them. When the denominators are different, make the parts the same size first.

Guide

Each bar is one whole. The blue parts are already coloured: that is what you have. The parts you shade turn orange: that is what you add.

When the denominators are the same, all the parts are the same size. So you just count parts: add the numerators and keep the denominator.

When the denominators are different, the parts are different sizes and you can't count them together. Use the + and − buttons to split the bar again until the parts are the same size. This is called finding a common denominator.