Solving puzzles faster for IBPS Clerk

Two candidates read the same puzzle. One finishes in four minutes, the other in nine, and the second one is not less intelligent. The difference is almost always the order in which they used the clues. The slow solver starts at clue 1 because it is first. The fast solver starts at the clue that places someone for certain.

Puzzles and seating sets usually make up the largest block of reasoning questions in both the prelims and the mains, and each set carries about five questions. Cutting two minutes from each set can add a whole extra set to your attempt. This guide shows how.

Why puzzles take so long

Most slow solves have one of three causes.

• Starting with a vague clue. "T is somewhere after P" leaves many possibilities open. Drawing them all wastes time.
• Redrawing. Solving one case to the end, finding it fails, then starting again from scratch.
• Not knowing when to stop. Spending eight minutes on a set that was never going to settle, while an easier set waits.

Each habit below attacks one of these.

Seven habits

1. Read all the clues once before drawing. Spend 20–30 seconds. You are looking for the definite clue and for clues that mention the same person.

2. Order clues by certainty.

3. Use compact notation. Write clues in your rough sheet in a shorthand you can read at a glance.

• "R = T + 1" for "R immediately after T"
• "S ✗ Wed" for "S not on Wednesday"
• "P < T" for "P before T"
• "Q, T: 2 between" for "two people between Q and T"

4. Draw cases side by side. When a clue allows two positions, draw two small grids next to each other and fill both as you go.

5. Kill cases early. After every new clue, check each case. Cross out a failed case at once so you stop looking at it.

6. Check against every clue. Before answering, run through all the clues on your final diagram. It takes 20 seconds and protects five answers.

7. The four-minute rule. If a set has not started to settle after about four minutes, mark it and move on. Come back only if time remains.

Clue ordering in action

Six people, P, Q, R, S, T and U, attend a training session on six days from Monday to Saturday, one person each day.

1. T attends on some day after P.
2. Only two people attend between Q and T.
3. S does not attend on Wednesday.
4. R attends on the day immediately after T.
5. P attends on Thursday.

The slow way. Start with clue 1. P could be on any day from Monday to Friday, and T on any later day. That is fifteen possible pairs before you have placed anyone.

The fast way. Use the clues in the order 5, 1, 4, 2, 3.

1. Clue 5 (definite): P is on Thursday.
2. Clue 1 (now linked): T is after Thursday, so T is on Friday or Saturday.
3. Clue 4 (linked): R is the day after T. If T were on Saturday, R would have no day. So T is on Friday and R on Saturday.
4. Clue 2: two people sit between Q and T. Counting forward from Friday runs out of days, so count back: Q is on Tuesday, with Wednesday and Thursday between them.
5. Clue 3 (negative): Monday and Wednesday remain for S and U. S is not on Wednesday, so S is on Monday and U on Wednesday.

Questions:

1. Who attends on Wednesday? U.
2. How many people attend between S and P? Two, Q and U.
3. Who attends immediately before T? P.

No cases, no redrawing. The same five clues read in their printed order would have opened fifteen possibilities on the first line.

Practice puzzle

Try it in under three minutes. Then check your answers and the solving order.

Six people, A, B, C, D, E and F, sit in a row facing north.

1. B sits third to the right of A.
2. C sits at one of the extreme ends of the row.
3. B is an immediate neighbour of C.
4. F sits somewhere to the left of A.
5. D is not an immediate neighbour of B.

Questions:

1. Who sits at the extreme left end?
2. Who sits second to the left of B?
3. Who sits exactly between A and E?
4. How many people sit between F and C?
5. Who sits to the immediate right of D?

Solution. Number the seats 1 to 6 from the left. Because everyone faces north, their right is your right.

1. Clues 2 and 3 together: C is at an end and B is next to C. If C were on seat 1, B would be on seat 2, and clue 1 would put A three seats to the left of seat 2, which does not exist. So C is on 6 and B on 5.
2. Clue 1: A is three seats left of B, so A is on 2.
3. Clue 4: F is left of A, so F is on 1.
4. Clue 5: D is not next to B, so D is not on 4. D is on 3 and E on 4.

Final row, left to right: F, A, D, E, B, C.

Answers:

1. F.
2. D. B is on 5, and two seats to the left is seat 3.
3. D. A is on 2 and E on 4.
4. Four. A, D, E and B.
5. E.

A four-week routine

Track two numbers each week: your average time per puzzle and how many sets you solved fully correct. A steady fall in time with no fall in accuracy means the method is working. If time falls but accuracy drops too, you are rushing, not getting faster.

Common mistakes

• Treating "immediately after" and "after" as the same clue.
• Drawing a big grid for a small puzzle. A single line of six days is enough for a scheduling set.
• Answering from a diagram with two open cases. If the question's answer differs between cases, the set is not solved yet.
• Skipping the final check because time is short. A wrong diagram costs every question in the set.

What to do next

• For one week, write the clue numbers in the order you plan to use them before drawing anything.
• Re-solve both puzzles on this page from memory of the clues alone.
• Practise floor puzzles and seating arrangement with a four-minute cap per set.
• Move on to mains-level sets in reasoning for the mains.