The four operations and BIDMAS
Adding, subtracting, multiplying and dividing, in the right order
Adding, subtracting, multiplying and dividing are your four main tools. Today we sharpen them and learn the order to use them in.
BIDMAS: the order of operations
When a calculation has more than one operation, work it out in this order:
- Brackets
- Indices (powers and roots)
- Division and Multiplication (left to right)
- Addition and Subtraction (left to right)
3 + 4 × 2 = 3 + 8 = 11 (not 14!)
Worked examples
Example 1. Work out 456 + 278.
Example 2. Work out 36 × 24.
Example 3. Work out (8 − 3) × 4 + 10 ÷ 2.
Top tips and common mistakes
- Check answers with the inverse: if 864 ÷ 24 = 36, your multiplication was right.
- Multiplication and division have equal priority: work left to right. 12 ÷ 3 × 2 = 4 × 2 = 8.
- Line up digits carefully in column methods.
BIDMAS tripped me up at first. Now I always look for brackets before I do anything else!
Practise
Answer as many as you like. Every question is new, and you get a “correct” tick for each one you get right first time. Use “Show answer” to see a worked solution.
Quiz: earn your stamp
Printable worksheet
The four operations and BIDMAS worksheet. The questions come first and the answers for grown-ups are on the last page, so you can print just the question pages.
Printing is optional. A4 size.