Reasoning and Mental Ability
This section tests reasoning and mental ability: series, analogy, coding-decoding, blood relations, direction sense, syllogism, seating arrangement, clocks and calendars. The aim is to find the rule, not to guess the answer.
Core rules
- In number series, check differences, ratios, squares, cubes and alternating patterns. In alphabet series, convert letters to positions A=1 to Z=26.
- Coding-decoding often uses letter shifts, reversal or word-to-number mapping. Write the given pairs side by side before inferring the rule.
- Blood relations: draw a family tree and mark gender. Use only the relationships stated; do not assume unstated relations.
- Direction sense: fix north, east, south and west; track left and right turns from the facing direction.
- Syllogism: a conclusion is valid only if it follows from all premises; common knowledge is irrelevant.
Worked example
A woman says, 'He is the son of my mother's only son.' The woman's mother's only son is her brother. The man is her brother's son, so he is her nephew. Reason: 'only son' fixes the brother, and 'son of' fixes the next generation.
Traps that cost marks
Do not assume a person's gender from a name. In direction questions, left and right depend on the direction faced. In syllogism, a possibility is not the same as a definite conclusion. Check whether the series uses two interleaved patterns.