Pulsars
0 %
Log inSign up

The order of operations

Operational priorities

What is 2 + 3 x 4 equal to?

Some say 20, others 14. Only one of the two is correct — and it’s not a matter of opinion: there is a rule, and everyone follows it, from calculators to computers.

The rule

We calculate in this order:

  1. What’s inside brackets
  2. Powers
  3. Multiplication and division
  4. Addition and subtraction

So 2 + 3 x 4 = 2 + 12 = 14. Multiplication takes precedence over addition.

The pitfall: from left to right

Within the same level of operations, we calculate from left to right. This is where most mistakes occur.

12 : 3 x 2   =  4 x 2   =  8      (and not 12 : 6 = 2)
10 - 4 - 3   =  6 - 3   =  3      (and not 10 - 1 = 9)

Division and subtraction are not ‘symmetrical’: the order matters.

Brackets take precedence over everything

2 + 3 x 4    = 14
(2 + 3) x 4  = 20

Brackets aren’t just for decoration: they change the result. When you’re in doubt, it’s always fine to add more.

Remember: if a calculation seems ambiguous to you, it isn’t — it just means you haven’t applied the rule yet. Write down the steps one by one.