Reasoning and Mental Ability
Reasoning and Mental Ability tests series, analogy, coding-decoding, blood relations, direction sense, syllogism, seating arrangement and non-verbal patterns. Speed comes from recognising the rule type, not from guessing.
Core rules
- Number series: check differences, ratios, squares/cubes and alternating series. Letter series: A=1 to Z=26; reverse position = 27 − forward position.
- Coding: compare word and code letter by letter; shifts may be +1, −2 or positional.
- Blood relations: draw a family tree; use + for male, − for female, horizontal for spouse, vertical for parent-child.
- Direction: fix north upward; right turn = clockwise 90°, left = anticlockwise 90°. Use Pythagoras for shortest distance.
- Syllogism: a valid conclusion must be true in every possible diagram; some does not imply all.
Worked example
Find the next term: 2, 6, 12, 20, 30, ?. Differences are 4, 6, 8, 10, increasing by 2. The next difference is 12, so the next term is 30 + 12 = 42. Alternatively, terms are 1×2, 2×3, 3×4, 4×5, 5×6, so the next is 6×7 = 42.
Traps
In blood relations, do not assume gender from a name or role. In direction questions, track the final facing direction separately from the final position. In syllogism, a possibility conclusion is not the same as a definite conclusion. In coding, apply the same shift consistently; one exception invalidates the pattern.