Simplification Cheat Sheet
31 Oct 2026
Quick answer
A quick revision cheat sheet on simplification and approximation for SSC, Banking, Railway and state exams. It covers the BODMAS order of operations, the order of brackets, the approximation method for fast answers, the algebraic identities, and the fraction and percentage values worth memorising to save time in the exam.
Simplification Cheat Sheet
Quick Revision
Simplification asks you to reduce a long expression to a single value. The whole topic rests on doing the operations in the correct order — the BODMAS rule.

Ready to practise? Take the Simplification quiz
1. BODMAS — the Order of Operations
Work through an expression in this order:
| Letter | Operation |
|---|---|
| B | Brackets |
| O | Of (and powers/roots) |
| D | Division |
| M | Multiplication |
| A | Addition |
| S | Subtraction |
Division and multiplication rank together (left to right), as do addition and subtraction.
Order of brackets: solve ( ) first, then { }, then [ ].
Example
12 + 6 ÷ 2 × 3 − 4
= 12 + 3 × 3 − 4 (division first)
= 12 + 9 − 4 (then multiplication)
= 172. Approximation (fast answers)
In "find the approximate value" questions, round each number to a convenient figure, then compute.
Example
49.8 × 20.1 ≈ 50 × 20 = 1000Round to the nearest easy number; the options are usually far enough apart to allow it.
3. Algebraic Identities
(a + b)² = a² + 2ab + b²
(a − b)² = a² − 2ab + b²
a² − b² = (a + b)(a − b)
(a + b)³ = a³ + 3a²b + 3ab² + b³
a³ + b³ = (a + b)(a² − ab + b²)
a³ − b³ = (a − b)(a² + ab + b²)4. Values Worth Memorising
- Squares up to 30 and cubes up to 15.
- Common fraction–percentage pairs: 1/2 = 50%, 1/4 = 25%, 1/5 = 20%, 1/8 = 12.5%, 1/3 = 33⅓%.
- Square roots of 2 ≈ 1.414, 3 ≈ 1.732.
These turn long divisions into instant recall.
5. Exam Quick Tips
- Always follow BODMAS; a wrong order is the most common mistake.
- Open round brackets first, then curly, then square.
- For "approximate value", round early and compute with easy numbers.
- Memorised squares, cubes and fraction-percents save the most time.
Keep revising with the rest of the Maths section:
How this was made: Drafted with AI assistance; spot-checked by the editor on 31 October 2026.