How the Reasoning section is built
Prelims has 35 Reasoning questions in 20 minutes. In Mains, Reasoning shares a 45-minute, 50-question, 60-mark section with Computer Aptitude. SBI's booklet calls it a test of "how well you can think".
The paper has two kinds of questions:
- Sets (puzzles, seating arrangements, input-output): 3 to 5 questions on one arrangement. Slow to set up, fast once solved.
- One-liners (inequality, syllogism, blood relations, direction, coding, series): independent questions, 20 to 40 seconds each.
Strategy follows from this: bank the one-liners quickly, then spend most of your time on the puzzles you choose carefully. A solved puzzle gives you all its questions at once, while an abandoned half-solved puzzle gives you nothing for the minutes spent.
A five-step method for puzzles
- Read the whole puzzle once and draw the frame: a line with positions, a circle, a floor table or a box stack.
- Place the definite clues first. "Q lives on floor 3" or "R sits at an extreme end" go straight onto the diagram.
- Use linked clues next. "T sits second to the right of Q" is definite once Q is placed.
- Make cases for uncertain clues. If "S sits at one of the ends" gives two options, draw two diagrams side by side. Strike out a case as soon as a clue contradicts it.
- Fill the leftover by elimination and check every clue once before answering.
Common puzzle and arrangement types
| Type | Frame to draw | Watch for |
|---|---|---|
| Linear seating (one or two rows) | A numbered line; for two rows, mark which way each row faces | Left and right flip when people face south |
| Circular seating | A circle with positions; arrow for facing direction | "Facing the centre" vs "facing outside" reverses left and right |
| Floor puzzles | A vertical table, floor 1 at the bottom | Whether the ground floor is numbered 1 or 0 |
| Box or stack | A vertical column | "Above" vs "immediately above" |
| Month, day or year based | A table of months or days in order | Months with 30 vs 31 days |
| Comparison or ranking | A single ordered line | "Second heaviest" counted from the right end |
Syllogism without confusion
Draw minimal Venn diagrams: show only what the statements force, nothing more. Then test each conclusion.
- "All A are B" and "All B are C" means "All A are C" follows.
- "Some A are B" and "No B is C" means "Some A are not C" follows.
- For "possibility" conclusions ("Some A being C is a possibility"), the answer is true unless the statements make it impossible.
- When neither "Some A are C" nor "No A is C" definitely follows, but together they cover every case, the answer is "either I or II follows".
Inequality: direct and coded
Combine statements only through a common element and only when the signs point the same way.
- A > B ≥ C gives A > C (a strict sign anywhere in the chain makes the result strict).
- A ≥ B ≥ C gives A ≥ C.
- A > B < C gives no relation between A and C.
- A = B and B ≥ C gives A ≥ C.
Either-or case: if the possible relation between A and C is "A ≥ C" and neither "A > C" nor "A = C" is definite alone, then "either A > C or A = C" follows.
In coded inequality, write the symbol meanings at the top of your rough sheet first, then decode every statement before solving.
Quick rules for other one-liners
| Topic | Rule of thumb |
|---|---|
| Blood relations | Draw a family tree: + for male, - for female, horizontal lines for siblings and couples, vertical for generations. |
| Direction and distance | Draw north up. Right turn when facing north takes you east. For shortest distance, use Pythagoras: 3 km and 4 km at right angles give 5 km. |
| Order and ranking | Total = rank from top + rank from bottom - 1. Rank 12 from top and 18 from bottom means 29 people. |
| Alphanumeric series | Write position numbers lightly over the series before counting "to the left" or "to the right". |
| Coding-decoding | Check letter shift (+1, -2), reverse order, and position value (A = 1, Z = 26). |
| Machine input-output | Find what changes in step 1 and step 2. Most machines sort by one rule per step. |
What changes in Mains
- Puzzles are longer and have more variables: eight or more people, several attributes, sometimes two puzzles linked.
- Logical reasoning appears: assumptions, conclusions, inferences, courses of action, cause and effect. Read the statement literally and do not use outside knowledge.
- Data sufficiency in reasoning tests whether the given statements are enough, not what the answer is.
- Computer Aptitude shares the time, so finish computer questions quickly to free minutes for puzzles.
How to practise
- Solve 3 to 4 puzzles a day, mixing types. Time each one.
- Do a 10-minute one-liner drill (inequality, syllogism, series) daily.
- For every puzzle you could not solve, re-solve it next day without a timer and write down which clue cracked it.
- In mocks, skim all puzzles first and start with the one with the most definite clues.
Questions about this
How many puzzle questions come in SBI Clerk Prelims?
In recent papers puzzles and seating arrangements together have usually carried around 10 to 15 of the 35 Reasoning questions. SBI does not fix the number.
How do I get faster at puzzles?
Use the same diagram style every time, place definite clues first, make cases early and practise 3 to 4 timed puzzles a day. Speed comes from repetition of one method.
Is Computer Aptitude part of Reasoning in Mains?
Yes. Mains has one section called Reasoning Ability & Computer Aptitude with 50 questions, 60 marks and 45 minutes.