Efficient addition and subtraction methods

Home learning focus

In this lesson, you will learn efficient methods for adding and subtracting from 4-digit numbers.

The lesson includes:

  • two videos
  • two activities

Created in partnership with Pearson.

Learn

These activities will teach you written methods for addition and subtraction, often called ‘column methods’.

However, sometimes it makes more sense to solve some additions and subtractions using a mental method.

The problems in this lesson all involve adding or subtracting multiples of ten, and the numbers are chosen carefully so that you can use a mental method to solve them.

You will learn how to look at a calculation and decide on the most efficient strategy to find the solution, rather than always reverting to a written method.

For example, to solve 700 – 1, it is more efficient to count back one than to write a full column subtraction!

Efficient addition and subtraction methods – Part a

In this video, learn to add hundreds to a 4-digit number using an efficient mental method.

Efficient addition and subtraction methods – Part b

In this video, learn to use efficient methods to add 1s, 10s and 1000s to a 4-digit number.

Practise

Activity 1

Addition and subtraction worksheet 1

This worksheet will help you practise adding and subtracting using efficient methods. Remember to think about what is changing in each calculation – the 1s, 10s, 100s or 1,000s?

Addition and subtraction worksheet 1

Click here for the answers.

Activity 2

Addition and subtraction worksheet 2

These problems all involve the same new skill, but they are applied in slightly different contexts. Look out for missing number problems!

Addition and subtraction worksheet 2

Click here for the answers.

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