Order of operation

 In this lesson we're going to learn the order of operation. The definition of order of operation is the agreement that mathematicians around the world agreed on a definite order of doing brackets and 4 operation (+ - x /) otherwise confusion would occur.

   The agreed order of operation

1. Work out the brackets first. (   )
2.Secondly, work out any multiplication or division as they occur from left or right.
3. Lastly, work out any addition or substitution as they occur from left or right.

The first example is 4+5x9

Like the agreement of the order of operation said:
Firstly we do the brackets first but there's no brackets,
so we're going to do the multiplication.

5x9=45
Then we do the addition. 45+4=49
Therefore the answer is 49.

The second example is 18-3x4+2

We do the multiplication first,-3x4=-12
secondly, we do addition and subtraction.18-12+2=8
Then our answer is 8.

Third and last example is 6+40/(9+1).
Firstly, we do the brackets first, (9+1)=10.
Secondly, we do multiplication or division, 40/10=4.
Third and last we do the additions, 6+4=10

Then the answer is 10.