Study Notes 2.3 Order of Operations
– When an equation comprises addition and subtraction only, we solve the operation from left to right.
E.g.
25 +67 – 9 = (25 + 67) – 9
= 92 – 9
= 83
– When an equation comprises multiplication and division only, we solve the operation from left to right as well
E.g
3 × 8 ÷ 6 =(3 × 8) ÷ 6
=24 ÷ 4
=4
– When an equation comprises all four operations , we solve the (+ – x ÷) operation by doing the multiplication OR division first followed by the addition OR subtraction from left to right .
E.g
70 + 4 × 3 − 7 = 70 + (4×3) −7
= 70 + 12 −7
= 82 -7
=75
-When an equation includes brackets, we do the operation inside the brackets first. Then we do the operations in the order as shown above.
E.g
66 −(10 × 4−16) +100 ÷5
=66 − (40−16) +(100 ÷5)
= 66 – ( 24 ) + ( 100÷ 5 )
=66 – 24 + 20
=62