Adding and Subtracting Decimals

Adding and Subtracting Decimals consolidates a primary-school skill at the start of NSW Year 7 maths, so it has no Stage 4 outcome of its own. The method is the same as for whole numbers: line up the decimal points, fill any gaps with zeros, then work column by column from the right.

You will estimate first, add and subtract without a calculator, find missing numbers by undoing, and check answers by adding back. Problems include change from a $20 note, relay swimming times, cutting a plank of wood and a temperature rising from below zero. It is part of Year 7 Decimals.