BIDMAS

MathematicsAQAEdexcelGCSEUnit: Number
Free taster
5 of 6 sections open
The basics

Why Order Matters

Why Order Matters

Imagine you're following a recipe: "Add 2 cups flour plus 3 times 4 tablespoons sugar". Do you add 2 + 3 = 5, then multiply by 4 to get 20 tablespoons sugar? Or do you multiply 3 × 4 = 12 first, then add 2 cups flour plus 12 tablespoons sugar? Without BIDMAS, mathematical expressions would be as confusing as this recipe! BIDMAS gives us the universal order that mathematicians worldwide follow.
BIDMAS - Brackets, Indices, Division, Multiplication, Addition, Subtraction order with worked examples
Spotlight
BIDMAS Order

Work through calculations in this order:

Exam tip

Earn the mark scheme marks

Exam Tips

  • Show your working: Write each step clearly to avoid mistakes and gain partial marks
  • Use brackets for clarity: (3 × 4) + 2 is clearer than 3 × 4 + 2
  • Check equal priority operations: For ÷ and ×, or + and -, always work left to right
  • Double-check indices: 2³ = 8, not 6. Powers are multiplication, not addition
  • Nested brackets: Work from inside out: 2 × (3 + (4 × 5)) = 2 × (3 + 20) = 2 × 23 = 46

Now try it yourself

Quiz · Question 1 of 14

What does the letter 'I' stand for in BIDMAS?

Tap an answer to check it

Revise every Mathematics topic, free during alpha

BIDMAS is one of 127 topics on PrepWise — all aligned to your exam board.

Start revising free →