3. Arithmetic operators

You are already familiar with many simple arithmetic operations: addition, subtraction, division and multiplication. The symbols used to represent these operations in a program are mostly the same ones you see in a maths textbook:-

+ for addition

- for subtraction

* for multiplication

/ for division

Arithmetic operators have two arguments, one on either side. Their position matters most for things like subtraction and division. 100/2 is very different from 2/100.

You can use multiple arithmetic operators on the same line, if you need to perform a complex calculation. The order that you carry out these calculations, called the 'order of operations' is BODMAS. This stands for

• Brackets first
• Order (numbers involving powers or square roots)
• Division
• Multiplication
• Addition
• Subtraction

This lets you work out expressions such as

$$x = 1 + ( 3 - 1) - 2^3+ 10/3 $$

in the same order that everyone else will use.