Order of Operations (BIDMAS/BODMAS) (OCR GCSE Maths) : Revision Note

Order of Operations (BIDMAS/BODMAS)

What is the order of operations (BODMAS/BIDMAS)?

• If there is more than one operation in a calculation then they should be done in the following order

  • Brackets: ( )

    • Perform any calculation(s) inside brackets first

  • pOwers or Indices (sometimes Order):  ², ³, √ and similar

    • These include powers, roots, reciprocals

  • Divisions or Multiplications: × or ÷

    • If there are more than one of these then work them out left to right

    • Division includes fractions

  • Additions or Subtractions: + or -

    • If there are more than one of these then work them out left to right

• The acronym BODMAS or BIDMAS can help you remember the order of operations

In what order should fractions and roots be dealt with?

• Fractions mean division in calculations (BODMAS/BIDMAS)

• There may be "invisible brackets" around the numerator and around the denominator

  • e.g.  means

  • Instead of brackets we extend the fraction line to show exactly what is on the top and what is on the bottom

• Roots are pOwers (BODMAS/BIDMAS)

• There may be "invisible brackets" under the root

  • e.g.  means

  • Instead of brackets we extend the top line on the root symbol to show everything that is to be rooted

How do I use a calculator for BIDMAS/BODMAS questions?

• Ensure that you enter a long or complicated calculation carefully

  • For most modern calculators, the calculation can be typed in exactly as it is written on paper 

  • You may need to use additional brackets on older calculators