Simplification Questions for SBI CLERK

BODMAS Rule — The Foundation

Every simplification problem follows a fixed order of operations called BODMAS. You must resolve operations in this exact sequence or you will get the wrong answer. Think of BODMAS as a strict queue — no cutting the line. The rule applies to every expression no matter how complex it looks.

• B — Brackets: solve innermost first, then curved (), then curly {}, then square []
• O — Of: means multiplication, e.g., 1/2 of 40 = 20
• D — Division: solve left to right
• M — Multiplication: solve left to right after division
• A — Addition: after all above are done
• S — Subtraction: last step

Fractions and Decimals

Many SBI Clerk questions involve mixed fractions, improper fractions, or a mix of fractions and decimals. The key skill is quick conversion and simplification. Always convert mixed fractions to improper fractions before operating. For decimals, align decimal points before adding or subtracting.

• Mixed to improper: 3 whole 2/5 = (3x5 + 2)/5 = 17/5
• To add fractions, find LCM of denominators
• Multiply fractions straight across numerator and denominator
• Dividing fractions: flip the second fraction and multiply (Keep Change Flip)
• Decimal tip: 0.25 = 1/4, 0.5 = 1/2, 0.75 = 3/4, 0.125 = 1/8 — memorize these

Squares, Cubes, and Surds

Knowing squares up to 30 and cubes up to 15 by heart saves 30 to 60 seconds per question. Surds (square roots, cube roots) appear in around 20 percent of simplification questions in SBI Clerk. You need not derive them — you must recall them instantly. Approximate if the answer choices are far apart.

• Squares: 1 to 30 must be memorized (e.g., 24 squared = 576, 27 squared = 729)
• Cubes: 1 to 15 must be memorized (e.g., 12 cubed = 1728, 13 cubed = 2197)
• Square roots of perfect squares: root 144 = 12, root 225 = 15, root 576 = 24
• Cube roots: cube root of 512 = 8, cube root of 1331 = 11
• Surd rule: root(a x b) = root(a) x root(b), useful to break down non-perfect surds

Percentages and their Fraction Equivalents

Percentage-based simplifications appear in two forms: direct percentage of a number, or multi-step expressions mixing percent with other operations. Knowing fraction-percent equivalents makes mental math lightning fast and is a big differentiator in the exam.

• 12.5% = 1/8, 16.67% = 1/6, 33.33% = 1/3, 66.67% = 2/3, 87.5% = 7/8
• x% of y = y% of x (swap trick saves time when one number is simpler)
• Percentage increase: (increase/original) x 100
• Successive percent: a% then b% overall = a + b + ab/100
• For quick calculation: 15% of 240 = 10% (24) + 5% (12) = 36

Approximation Technique

SBI Clerk often has a dedicated Approximation section (5 questions) where you must find the nearest value, not the exact answer. The trick is to round numbers smartly — round one up and one down to keep balance. Do not waste time computing exact values when the choices are spread far apart.

• Round to nearest 10 or 100 depending on the magnitude of numbers
• If rounding up in one place, round down in another to stay close to true value
• Check answer choices first — if they differ by 50 or more, rough rounding is enough
• For roots, identify the two perfect squares the number falls between
• Never approximate when question says 'exact value' — only when it says 'approximately'

• Ignoring BODMAS order — doing addition before multiplication because it appears first in the expression. Always multiply/divide before add/subtract.
• Treating 'of' as addition instead of multiplication. '20% of 50' is 20/100 x 50, not 20 + 50.
• Forgetting to resolve innermost brackets first — jumping to the square bracket before finishing round bracket.
• Sign errors after opening brackets: -(a - b) = -a + b, not -a - b. Minus outside flips signs inside.
• Using approximation in Simplification questions and exact method in Approximation questions — do the opposite of what the question requires.

• BODMAS mnemonic: Big Orange Dinosaurs Munch All Snacks — Brackets, Of, Division, Multiplication, Addition, Subtraction
• Keep Change Flip for fraction division: Keep the first fraction, Change division to multiplication, Flip the second fraction
• Percent-Fraction cheat sheet as a song: One-eighth is 12.5, one-sixth is 16.67, one-fifth is 20, one-fourth is 25 — sing it until automatic
• For approximation, think of a see-saw — if you round one number up, round another down to keep balance

• SBI Clerk Prelims typically has 5 Simplification and 5 Approximation questions in the Quant section. Together that is 10 easy marks — target all 10 within 8 to 10 minutes.
• Approximation questions in SBI Clerk tend to have expressions with large square roots or cube roots. Practice estimating root values between perfect squares.
• Simplification questions rarely need calculators if you know fraction-percent equivalents and square/cube tables. Raw calculation is the bottleneck — drill tables daily.
• Recent SBI Clerk papers have mixed bracket expressions with decimals and fractions in the same question — practice these combined forms, not just pure BODMAS.
• In Prelims, accuracy beats speed here. One wrong simplification answer costs 0.25 marks plus wastes time you spent. Double-check bracket signs before moving on.