# Help Your Child Understand the Mental Maths for Subtraction

Subtraction can be confusing to a young child, but if they have learned the mental maths strategies for addition it’s easier. Once your child understands the Mental Maths patterns of Addition, then they can apply them to subtraction.

## Subtraction is really addition

One mental math strategy is that subtraction is really addition.

**How does this work?**

Solving a subtraction problem such as 10 – 2 is the same as answering the question “2 + what number = 10?”. Figure out the missing number and you have easily figured out a subtraction problem.. You can always change any subtraction problem into an addition problem.

## Counting back

Counting back is the opposite of the counting forward learned in addition. With this your child counts back to get the answer starting with the larger number. For example, 14-3, the learner would count 14,13,12, the answer is 11.

You can start younger children learning this with blocks or sticks so they can see the answer. Once they get familiar with it they can start to solve subtraction problems in their head.

## Doubles with subtraction

Once the addition of doubles is mastered use doubles to solve 12-6 or 10-5. As your child becomes automatic with subtracting doubles. they can use this to solve more complicated subtraction. For example, 15-7 think 15 is one more than that the double of 7 so the answer is one more than 7 which is 8.

## Using 10

10 is often called the friendly number in mathematical terms. It’s an easy number to work with. As kids get more familiar with numbers they can substitute 10 and adjust the answer. For example let’s use the equation 19-7. Students think 10-7 which is a difference of 3. They then add on the remaining 9 from the larger equation which gives them 3+9=12.

Doing a subtraction using 10 makes calculating with larger and odd numbers much quicker.

Sorry, comments are closed for this post.