Reasoning and Mental Ability
What is tested
Reasoning and Mental Ability checks pattern detection and logical consistency. Common topics are number and letter series, analogies, coding-decoding, blood relations, direction sense, syllogism, seating arrangement, ranking, and non-verbal reasoning. The exam favours short puzzles that can be solved by writing a table or diagram rather than by guessing.
Core approaches
- Series: check differences, then ratios, then alternating patterns. Do not fix on one operation too early.
- Coding: compare the same letter's position in the word and code; note shifts such as +1, +2, or reversal.
- Blood relations: draw a family tree; use + and - or male and female markers to avoid confusion.
- Direction: fix north and plot each turn; final direction is not the same as final displacement.
- Syllogism: draw minimum overlapping circles; a conclusion is valid only if it must be true in every diagram.
- Seating: start with fixed positions and immediate neighbours, then place uncertain people.
Worked example
Find the next term: 2, 6, 12, 20, 30, ?. Reason: differences are 4, 6, 8, 10; the differences increase by 2. The next difference is 12, so the next term is 30 + 12 = 42. Alternatively, the terms are 1x2, 2x3, 3x4, 4x5, 5x6, so the next is 6x7 = 42. Both patterns agree, which confirms the answer.
Traps that cost marks
Do not assume a series is arithmetic before checking a second difference. In blood relations, do not confuse maternal and paternal sides. In syllogism, do not use real-world knowledge; use only the statements. In direction questions, track left and right relative to the facing direction.