Reasoning Ability
Reasoning Ability in FCI AG-III carries 20 questions in Phase I and 25 in Phase II. It checks logical structure, not memorised facts: analogy and classification, number and alphabet series, coding-decoding, blood relations, direction sense, syllogism, seating arrangement, puzzles, and non-verbal items such as mirror images and embedded figures.
Core rules
- In series, test differences, ratios, squares/cubes, and alternating patterns before assuming a single rule.
- Coding-decoding: map each letter's shift separately; check whether the shift is constant, positional (A=1), or reversed.
- Blood relations: draw a family tree with gender marks; do not assume gender from a relation word unless stated.
- Direction sense: fix north upward; a right turn from north is east; track net displacement with Pythagoras when paths are perpendicular.
- Syllogism: use Venn diagrams. 'All A are B' does not convert to 'All B are A'; 'No A is B' converts to 'No B is A'.
- Seating: fix one person and orient left/right from that person's facing direction.
Worked example
Find the next term: 2, 6, 12, 20, 30, ? Differences: 6−2=4, 12−6=6, 20−12=8, 30−20=10. The differences rise by 2, so the next difference is 12; 30+12=42. Equivalently, terms are 1×2, 2×3, 3×4, 4×5, 5×6, so next is 6×7=42.
Traps
- Forcing an arithmetic progression when the series alternates.
- Ignoring 'facing north/south' in seating arrangements.
- Treating 'either-or' syllogism conclusions as always valid.
- In direction questions, turning left after moving south changes the axis; sketch it.