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Addition Tips and Tricks

Learning to add numbers in your head is an essential part of your child’s math journey. There are a number of methods students can use to make adding numbers using mental math much easier. Here we share some of those addition tips and tricks.

Friendly numbers

For this technique, imagine a number line. You make a ‘friendly’ number first and then add the rest. Let us show you how.

For example: 17 + 7

Making a friendly number means a number ending in 0.
For 17, that friendly number is 20.
You borrow 3 from 7 to make it 20.
That means you have 4 left: 7 – 3.
Here’s how that looks on a number line:

friendly numbers mental math

Stealing numbers

At times it’s easier to ‘steal’ a number; let us show you how.

For example: 59 + 86

stealing numbers mental math

Compensation Method

In compensation you round up a number – to make it easier to add – and then take away the extra after you have added.

For example: 29 + 16

 It’s easier to round up the 29 to 30, and then take away the extra 1:

compensation method mental math

Break apart by place value

Sometimes it may be easier to deal with the numbers by place value: adding the tens together, adding the ones together and adding the total numbers.

For example: 36 + 72

break apart by place value mental math
Now let’s re-group the numbers into tens and ones. Add the tens and ones separately.

place value break apart mental math
Now it’s easier to do the final sum: 100 + 8 = 108

To practice these methods, we have a selection of mental addition worksheets in our grade 4 math section.