Ever wondered why your calculator gives a different answer than... Show more
Understanding BIDMAS/BODMAS: The Order of Operations Explained










The Order of Operations
BIDMAS and BODMAS are two names for the same thing - they're your roadmap for solving tricky maths problems correctly. Think of them as the "highway code" for mathematics that everyone follows to get the same answer.
The letters stand for the order you should tackle different parts of a calculation. B means Brackets, I or O means Indices/Orders, D is Division, M is Multiplication, A is Addition, and S is Subtraction.
Quick Tip: Remember BIDMAS with "Big Ideas Don't Mean Anything Sometimes" or BODMAS with "Big Old Dogs Make Awful Smells"!

Brackets Come First
Brackets are your number one priority - always sort out what's inside them before doing anything else. They're like VIP guests that get served first at a restaurant.
Take 2×(2+8) as an example. You can't just work left to right here. First, you solve what's in the brackets: 2+8 = 10. Then you multiply: 2×10 = 20.
If you ignored the brackets and did 2×2 first, you'd get a completely wrong answer. That's why brackets are so important!
Remember: Brackets are like instructions saying "do me first!" - never ignore them.

Indices, Orders, and Powers
Indices (or Orders) are things like square numbers, cubed numbers, and square roots. These little superscript numbers pack a punch and need sorting out early.
For 3²+5, you don't multiply 3×2. Instead, 3² means 3×3 = 9. Then you add 5 to get 14.
Powers and roots might look small, but they have huge effects on your final answer. Miss them and you'll be miles off!
Watch Out: 3² means "3 times itself" (3×3), not "3 times 2" - this trips loads of people up!

Division and Multiplication
Division and multiplication work as a team - they're at the same level of importance and you work through them from left to right.
Let's try (3×5)÷15. The brackets tell you to do 3×5 = 15 first. Then you divide: 15÷15 = 1.
When you see both multiplication and division in the same problem, just work from left to right. Don't automatically do all multiplication before division - they're equal partners!
Pro Tip: Division and multiplication are like dance partners - they move together from left to right across your calculation.

Addition and Subtraction
Addition and subtraction are the final pair, and like division and multiplication, you handle them from left to right when they appear together.
For 6+7-8, you work left to right: first 6+7 = 13, then 13-8 = 5. Don't do all additions before subtractions - treat them as equals.
These operations might seem simple, but getting their order wrong can still mess up your whole answer. Every step in BIDMAS matters!
Key Point: Addition and subtraction work as a team too - always go from left to right when you see them together.




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Understanding BIDMAS/BODMAS: The Order of Operations Explained
Ever wondered why your calculator gives a different answer than you do for the same sum? It's all about following the right order when doing maths operations. BIDMAS (or BODMAS) is like a set of rules that tells you exactly... Show more

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The Order of Operations
BIDMAS and BODMAS are two names for the same thing - they're your roadmap for solving tricky maths problems correctly. Think of them as the "highway code" for mathematics that everyone follows to get the same answer.
The letters stand for the order you should tackle different parts of a calculation. B means Brackets, I or O means Indices/Orders, D is Division, M is Multiplication, A is Addition, and S is Subtraction.
Quick Tip: Remember BIDMAS with "Big Ideas Don't Mean Anything Sometimes" or BODMAS with "Big Old Dogs Make Awful Smells"!

Sign up to see the content. It's free!
- Access to all documents
- Improve your grades
- Join milions of students
Brackets Come First
Brackets are your number one priority - always sort out what's inside them before doing anything else. They're like VIP guests that get served first at a restaurant.
Take 2×(2+8) as an example. You can't just work left to right here. First, you solve what's in the brackets: 2+8 = 10. Then you multiply: 2×10 = 20.
If you ignored the brackets and did 2×2 first, you'd get a completely wrong answer. That's why brackets are so important!
Remember: Brackets are like instructions saying "do me first!" - never ignore them.

Sign up to see the content. It's free!
- Access to all documents
- Improve your grades
- Join milions of students
Indices, Orders, and Powers
Indices (or Orders) are things like square numbers, cubed numbers, and square roots. These little superscript numbers pack a punch and need sorting out early.
For 3²+5, you don't multiply 3×2. Instead, 3² means 3×3 = 9. Then you add 5 to get 14.
Powers and roots might look small, but they have huge effects on your final answer. Miss them and you'll be miles off!
Watch Out: 3² means "3 times itself" (3×3), not "3 times 2" - this trips loads of people up!

Sign up to see the content. It's free!
- Access to all documents
- Improve your grades
- Join milions of students
Division and Multiplication
Division and multiplication work as a team - they're at the same level of importance and you work through them from left to right.
Let's try (3×5)÷15. The brackets tell you to do 3×5 = 15 first. Then you divide: 15÷15 = 1.
When you see both multiplication and division in the same problem, just work from left to right. Don't automatically do all multiplication before division - they're equal partners!
Pro Tip: Division and multiplication are like dance partners - they move together from left to right across your calculation.

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- Access to all documents
- Improve your grades
- Join milions of students
Addition and Subtraction
Addition and subtraction are the final pair, and like division and multiplication, you handle them from left to right when they appear together.
For 6+7-8, you work left to right: first 6+7 = 13, then 13-8 = 5. Don't do all additions before subtractions - treat them as equals.
These operations might seem simple, but getting their order wrong can still mess up your whole answer. Every step in BIDMAS matters!
Key Point: Addition and subtraction work as a team too - always go from left to right when you see them together.

Sign up to see the content. It's free!
- Access to all documents
- Improve your grades
- Join milions of students

Sign up to see the content. It's free!
- Access to all documents
- Improve your grades
- Join milions of students

Sign up to see the content. It's free!
- Access to all documents
- Improve your grades
- Join milions of students

Sign up to see the content. It's free!
- Access to all documents
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- Join milions of students
We thought you’d never ask...
What is the Knowunity AI companion?
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
Where can I download the Knowunity app?
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Explore in-depth analysis and key quotes for characters in J.B. Priestley's 'An Inspector Calls'. This resource covers Gerald Croft, Inspector Goole, Sheila Birling, Mrs. Birling, Eric Birling, and Eva Smith, focusing on themes of class, gender roles, and social responsibility. Ideal for students aiming for Grade 8 and above.
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Explore the complex themes of guilt and ambition in Shakespeare's 'Macbeth'. This analysis covers key characters, including Macbeth and Lady Macbeth, their moral dilemmas, and the tragic consequences of their ambition. Ideal for students studying character motivations, thematic elements, and the psychological impact of power. Includes insights on the natural order, manipulation, and the descent into madness.
Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
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