Intelligence / Reasoning
Intelligence (reasoning) is a 25-question, 50-mark AISSEE section (2 marks each, one-third negative marking). It tests pattern recognition rather than syllabus knowledge: number and letter series, analogies, classification/odd-one-out, coding-decoding, blood relations, direction sense, ranking, and non-verbal items such as mirror images, water images, paper folding and figure series. Speed matters, but accuracy matters more because a wrong answer deducts two-thirds of a mark.
Core methods
- Series: write the differences between consecutive terms; if differences are not constant, check second differences, squares, cubes or alternating operations.
- Analogy: state the relationship in a sentence ('X is the square of Y') before applying it to the new pair.
- Coding: number the alphabet A=1 to Z=26; for shift codes, check whether the shift is forward, backward or alternating.
- Blood relations: draw a family tree; use + for male and − for female; never assume gender from a name.
- Direction: draw a compass cross; after a right turn from north you face east.
Worked example
Find the next term: 2, 6, 12, 20, 30, ? Differences: 4, 6, 8, 10 - increasing by 2 each time. The next difference is 12, so the next term is 30 + 12 = 42. Equivalently, the terms are 1×2, 2×3, 3×4, 4×5, 5×6, so the next is 6×7 = 42. Confirming with two rules is a useful check.
Traps that cost marks
Assuming a constant difference after only two terms; forgetting the starting point in direction puzzles; treating 'brother of my father's sister' as a direct relation without drawing it; and reversing only left-right for a mirror image but also flipping top-bottom by mistake. In non-verbal items, compare one feature at a time: shape, size, rotation, shading, position.