In order to establish the basics needed to do all mathematics, we will use the acronym:
B.I.D.M.A.S.

This refers to the order in which the parts of an equation must be undertaken. The letters stand for:

Brackets – ( )
Indices – when a number is squared, cubed etc.
Division
Multiplication
Addition
Subtraction.

The best way to explain this is to work through some examples.

1.

3 + (6 / 3) = ?

If the brackets were not done first, the answer to this question would be 3 + 6 + 3 which is 12. The rule BIDMAS means that the brackets must be done first, meaning that the brackets in the equation then become 2. The equation then reads 3 + 2 which is 5, not 12. 5 is the correct answer.

2.

18 – 6 / 3 = ?

If the equation is done working from left to right the answer is 4. This is not correct however, as using the BIDMAS rule the division section of the equation has to be done first. When correctly applied the equation reads 18 – (6 / 3) or 18 – 2 which is 16.

It is very important to follow the order that the BIDMAS rule provides, elimination each letter as the equation determines. So for all equations the numbers in the brackets must be dealt with first, if there are no brackets then the indices must be calculated first, and so on.

Don’t forget! BIDMAS