It’s November, and for this month I’m going to be looking at algebra. So many people fear algebra but there are so many ways to help you conquer it. Today I want to focus on the order of operations, as if you don’t understand this you will not be able to do Algebra, or indeed any maths!

When we teach maths in the UK to start with, you do the maths from left to right, but anything in brackets is done first. Then when children get to year 5/6/7 we teach them the mathematical order of precedence, or the ‘order of operations’ more commonly known as BIDMAS or BODMAS or in the US PEDMAS.

I do sometimes wonder why we teach it so late, as I’ve found that if it isn’t embedded and explained that this is the order ALL maths is calculated, young people will only use it when they are told to.

So 

Let’s look at this sum:

3 + 2 x 4   

If we work left to write 3 + 2 is 5, and 5 x 4 is 20.

But if we do 2 x 4 first we get 8, then +3 and we have 11. 

The reason that we have the rule is to have no ambiguity. You know how addition can be done in any order (it’s commutative), well this means the sum is the same either way of the addition.

2 x 4 + 3 is the same as 3 + 2 x 4, keeping that property.