Example 1
What approximate value should come in place of ?: 24.04 × 13.97 + 339.2 = ?
Answer: D) 675
Round each number: 24 × 14 + 339 = 675 (exact value 675.04).
Approximation questions for competitive exams: rules, worked examples and practice
Approximation questions ask for the nearest value of a messy calculation. Round each number sensibly, then calculate; the options are usually far enough apart.
Key rules and formulas
- Round to numbers that are easy to multiply or divide (e.g. 49.8 → 50, 7.97 → 8).
- Use known squares, cubes and percentage-fractions (12.5% = 1/8).
- Round some numbers up and some down so the errors cancel.
- Check the order of magnitude against the options first.
Common traps
- Rounding every number in the same direction.
- Ignoring the order of operations (BODMAS) after rounding.
Where Approximation is asked
- IBPS Clerk Prelims (Numerical Ability)
- IBPS PO Prelims (Quantitative Aptitude)
- SBI Clerk Prelims (Numerical Ability)
- SBI PO Prelims (Quantitative Aptitude)
Worked examples
Example 2
What approximate value should come in place of ?: 45.04 × 14.97 + 374.2 = ?
Answer: C) 1,049
Round each number: 45 × 15 + 374 = 1,049 (exact value 1,048.45).
Example 3
What approximate value should come in place of ?: 25.04 × 24.97 + 350.2 = ?
Answer: A) 975
Round each number: 25 × 25 + 350 = 975 (exact value 975.45).
Frequently asked questions
What is Approximation in competitive exams?
Approximation questions ask for the nearest value of a messy calculation. Round each number sensibly, then calculate; the options are usually far enough apart.
Which exams ask Approximation questions?
On MockBazaar, Approximation questions appear in IBPS Clerk Prelims, IBPS PO Prelims, SBI Clerk Prelims, SBI PO Prelims.
What is the most common mistake in Approximation?
Rounding every number in the same direction.