Reasoning: Pattern Recognition Under Time Pressure
Section B of the C-CAT is the reasoning paper: a large bank of short, independent items to be cleared in roughly an hour. Nothing is solved by long formal proofs; nearly everything yields to a recognised pattern. Typical families are number and letter series, analogies, coding–decoding, blood relations, direction sense, syllogism, seating and ranking puzzles, clocks and calendars, data sufficiency, and non-verbal items such as figure series, mirror images and embedded figures.
Core patterns
- Series: check first differences, then ratios, then squares and cubes with a small constant added or subtracted; try alternating sub-series for even and odd positions.
- Letter series: convert to positions (A=1 … Z=26) or reverse pairs (A↔Z, B↔Y) and do arithmetic on the numbers.
- Coding–decoding: look for a fixed shift, reversal of the word, or letters replaced by their position values.
- Blood relations: draw a compact family tree, marking gender with + and −, and never hold the tree in your head.
- Direction sense: fix North on the page, track net displacement, and finish with Pythagoras when the path turns at right angles.
- Ranking: total = (rank from left) + (rank from right) − 1.
- Clock angle = |30H − 5.5M|, using the hour and minute readings.
Worked example
Series: 3, 10, 29, 66, ?. First differences are 7, 19, 37; second differences 12, 18 are not constant, so a single-step rule fails. Test cubes: 1³+2=3, 2³+2=10, 3³+2=29, 4³+2=66, so the next term is 5³+2=127. Spotting that 3, 10 and 29 sit one or two away from 1, 8 and 27 is far quicker than extending a difference table.
Traps that cost marks
- Rejecting a syllogism conclusion that is only possible when the question asks what can be true.
- Turning left or right relative to the page instead of relative to the person's current facing direction.
- Assuming "my father's only son" is someone other than the speaker.
- Over-extending a clean one-step pattern without testing it against the last given term.