Simplification Questions for IBPS RRB CLERK

BODMAS Rule — The Foundation

Every simplification question follows a fixed order of operations. BODMAS stands for Brackets, Orders (powers and roots), Division, Multiplication, Addition, Subtraction. You must solve in exactly this sequence or you will get the wrong answer. Think of it like a queue — you cannot jump the line.

• Brackets first — solve innermost bracket first, then move outward: (), {}, []
• Orders next — square roots, cubes, powers before anything else
• Division and Multiplication are equal priority — solve left to right
• Addition and Subtraction are equal priority — solve left to right
• Never add before you multiply — the most common exam trap
• If no bracket is given, always scan the entire expression before touching it

Fractions and Decimals

Many simplification questions involve a mix of fractions and decimals. The trick is to convert everything to either fractions or decimals before operating. Decimals are faster when numbers are clean; fractions are better when you see recurring terms. Learn your fraction-to-decimal table by heart — it saves 20 to 30 seconds per question.

• 1/2 = 0.5, 1/4 = 0.25, 3/4 = 0.75, 1/5 = 0.2, 1/8 = 0.125
• 1/3 = 0.333, 2/3 = 0.667 — keep as fractions when possible
• To add fractions, take LCM of denominators first
• Mixed numbers like 3 and 1/4 should be converted to improper fractions: 13/4
• When dividing fractions, flip the second fraction and multiply: (a/b) / (c/d) = (a/b) x (d/c)

Surds and Indices

Surds are square roots or cube roots that cannot be simplified to whole numbers. Indices are powers. IBPS RRB clerk level questions on this are straightforward — you will not face advanced surd rationalization. Focus on basic rules for powers and recognizing perfect squares and cubes quickly.

• Perfect squares to memorize: 1 to 30 squared — especially 12 to 25
• Perfect cubes to memorize: 1 cube=1, 2=8, 3=27, 4=64, 5=125, 6=216, 7=343
• a^m x a^n = a^(m+n), a^m / a^n = a^(m-n)
• (a^m)^n = a^(m x n)
• a^0 = 1 for any non-zero a
• Square root of (a x b) = root(a) x root(b) — use to simplify surds

Approximation — The Speed Hack

Approximation questions look like simplification but the answer choices are spread far apart — usually differing by 50 or more. The exam expects you to round numbers to nearest tens or hundreds and calculate fast. Do not waste time on exact calculation here. If the options are 280, 320, 370, 420 and your approximation gives 315, mark 320 confidently.

• Round to nearest 10 for most questions — do not over-calculate
• Square root approximation: find nearest perfect square and adjust slightly
• If options are very close (within 5), only then do exact calculation
• Always check if the question says 'approximately' — that is your green signal to round
• Typical structure: large decimal + fraction x big number — convert and round

• Solving left to right without following BODMAS — adding before multiplying is the number one error that kills marks
• Forgetting to solve the innermost bracket first when multiple brackets are nested
• In approximation, over-rounding: rounding 67 to 100 instead of 70 leads to wrong option selection
• Dividing fractions incorrectly by dividing numerators and denominators directly instead of flipping and multiplying
• Treating a^m x b^m as (ab)^(2m) — remember you can combine bases only when exponents are same, not bases

• BODMAS = Big Orange Dogs Make Awful Sounds — Brackets, Orders, Division, Multiplication, Addition, Subtraction
• Flip and Multiply for fraction division — think of a traffic U-turn: the second fraction does a U-turn before you multiply
• Squares 1 to 15: 1,4,9,16,25,36,49,64,81,100,121,144,169,196,225 — chant them like a phone number every morning
• For approximation: SPREAD CHECK — if options are spread wide, round boldly; if they are close, calculate exactly

• IBPS RRB Clerk Prelims 2023 and 2022 both had 5 pure simplification and 5 approximation questions in the Quant section — that is 10 marks up for grabs with the right practice
• These questions appear in the first half of the Quant section — solve them first to build confidence and save time for DI
• Difficulty level is easy to moderate — a well-prepared aspirant should finish each question in 30 to 45 seconds maximum
• Approximation questions often use square roots of non-perfect numbers like root(195) or root(360) — practice estimating these by bracketing between two perfect squares
• Never skip a simplification question in the exam — it is almost always solvable and guessing here is unnecessary; these are free marks if you know BODMAS cold