Maths

Subtraction Calculations

There are many different ways to subtract numbers from one another. It is

important to choose a method that works quickly and easily for you. For

subtracting two whole numbers, you may choose to do the sum in your head.

If you want to write it down, you can choose to use a number line. You start

with the number that is being taken away and count upwards to the original

number.

Example 1. Let’s say the question you’ve been given is 83 – 37 =? This is how we would set up the number line: We then could add up the differences 3 + 40 + 3 = 46 We can check this is the right answer by adding 46 and 37 37 + 46 = 83 so we know that 46 is definitely the right answer. |

If you don’t want to use a number line, especially on larger numbers, it may

be easier for you to use the column method for subtraction.

Like in the addition method, we have to first line up the digits in the correct

place value then begin the subtraction in the units column.

However, if we don’t have a larger number on the top of the column we have

to borrow from the next column.

Example 2. |

Let’s say that the question we’ve been given is 925 – 264 =?

This is how we would do the sum:

These methods would also work with decimal numbers but if you find

decimals difficult, it might be easier for you to treat them as whole numbers

during the calculation.

Related Topics

Place-value Ordering Numbers Polygons

Rounding Numbers Quadrilaterals Addition-Calculations