Simplification
Master important formulas and concepts with our comprehensive guide
Important Formulas & Concepts
Study MaterialSimplification
Simplification is one of the most important and high-scoring topics in Quantitative Aptitude. Questions from simplification are frequently asked in SSC, Banking, Railway, CDS, NDA, CAT, UPSC, and various competitive examinations.
This chapter focuses on reducing complex mathematical expressions into simpler forms by applying arithmetic operations in the correct sequence. Strong command over simplification techniques improves calculation speed, accuracy, and overall aptitude performance.
Why Simplification is Important?
- High-weightage topic in competitive exams.
- Improves calculation speed significantly.
- Foundation for arithmetic and algebra problems.
- Useful in approximation and numerical ability tests.
- Helps solve lengthy calculations quickly and accurately.
What is Simplification?
Simplification is the process of converting a complex mathematical expression into a simpler form by performing arithmetic operations according to a specific order.
A mathematical expression may contain:
- Addition (+)
- Subtraction (−)
- Multiplication (×)
- Division (÷)
- Brackets
- Fractions
- Roots and powers
To solve such expressions correctly, we follow the VBODMAS Rule.
VBODMAS Rule
VBODMAS defines the correct order of operations in arithmetic expressions.
VBODMAS Stands For
| Letter | Meaning | Operation |
|---|---|---|
| V | Vinculum | Bar or Line |
| B | Bracket | () {} [] |
| O | Of | Multiplication with Fractions/Percentages |
| D | Division | ÷ |
| M | Multiplication | × |
| A | Addition | + |
| S | Subtraction | − |
✔ Operations are always performed from left to right.
✔ Follow the exact sequence of VBODMAS to avoid mistakes.
Order of Solving Brackets
If multiple brackets are present, solve them in the following order:
- Vinculum (Bar)
- Small Bracket ()
- Curly Bracket {}
- Square Bracket []
Example:
[12 + {8 − (3 × 2)}]
First solve:
(3 × 2) = 6
Then:
{8 − 6} = 2
Finally:
12 + 2 = 14
Vinculum (Bar) Concept
A vinculum is a horizontal bar placed over numbers or expressions.
Operations under the vinculum are solved first.
Example:
8 + 3 + 2 × 4
First solve the vinculum:
3 + 2 = 5
Then:
8 + 5 × 4
= 8 + 20
= 28
Concept of "Of"
The word "of" means multiplication.
According to VBODMAS, "of" is solved before division and multiplication.
Example:
2/3 of 18
= (2/3) × 18
= 12
Basic Arithmetic Operations
1. Addition
Combining two or more numbers to get a total value.
Example:
25 + 18 = 43
2. Subtraction
Finding the difference between numbers.
Example:
56 − 19 = 37
3. Multiplication
Repeated addition of a number.
Example:
12 × 5 = 60
4. Division
Splitting a quantity into equal parts.
Example:
84 ÷ 7 = 12
Fractions in Simplification
Fractions are solved by:
- Finding LCM of denominators
- Reducing into simplest form
- Applying VBODMAS sequence
Example:
1/2 + 1/3
LCM of 2 and 3 = 6
= 3/6 + 2/6
= 5/6
Decimal Operations
While solving decimal expressions:
- Align decimal points correctly.
- Count decimal places carefully.
- Apply VBODMAS sequence properly.
| Expression | Answer |
|---|---|
| 12.5 + 7.25 | 19.75 |
| 5.2 × 0.5 | 2.6 |
| 18.6 ÷ 3 | 6.2 |
Square and Cube Concepts
Squares
Square of a number = Number × Number
| Number | Square |
|---|---|
| 12 | 144 |
| 25 | 625 |
| 30 | 900 |
Cubes
Cube of a number = Number × Number × Number
| Number | Cube |
|---|---|
| 2 | 8 |
| 5 | 125 |
| 10 | 1000 |
Important Algebraic Identities
| Identity | Formula |
|---|---|
| Square of Sum | (a + b)² = a² + b² + 2ab |
| Square of Difference | (a − b)² = a² + b² − 2ab |
| Difference of Squares | (a + b)(a − b) = a² − b² |
| Cube Sum Identity | a³ + b³ = (a + b)(a² − ab + b²) |
| Cube Difference Identity | a³ − b³ = (a − b)(a² + ab + b²) |
Absolute Value of a Real Number
The absolute value of a real number is always non-negative.
It represents the distance of the number from zero.
|m| = m, if m > 0
|m| = −m, if m < 0
| Expression | Value |
|---|---|
| |5| | 5 |
| |−5| | 5 |
| |12| | 12 |
Important Simplification Formulae
| Concept | Formula |
|---|---|
| Square of Number | a² = a × a |
| Cube of Number | a³ = a × a × a |
| Difference of Squares | a² − b² = (a + b)(a − b) |
| Average Formula | Average = Sum / Number of Terms |
| Fraction Addition | a/b + c/d = (ad + bc)/bd |
Important Exam Tips
- Always follow VBODMAS sequence strictly.
- Solve brackets carefully from inner to outer.
- Practice multiplication tables, squares, and cubes regularly.
- Use algebraic identities for fast calculations.
- Be careful while handling negative signs.
- Simplify fractions before multiplication whenever possible.
- Use approximation techniques in lengthy calculations.
Simplification is one of the most scoring chapters in Quantitative Aptitude. Strong command over VBODMAS, arithmetic operations, fractions, decimals, and algebraic identities helps candidates solve aptitude questions quickly and accurately in competitive examinations.