Numerical ability and logical reasoning — the speed-and-accuracy section of the paper.
Number systems & divisibility rules, order of magnitude, HCF & LCM, and powers, exponents, squares, square roots and cube roots form the toolkit for faster calculation elsewhere. BODMAS (Brackets, Orders, Division/Multiplication, Addition/Subtraction) governs the order of operations in any simplification problem involving multiple operators.
Ratio, proportion & mixtures (including alligation-style mixture problems), arithmetic mean, weighted mean, median, mode, and geometric & harmonic mean (each with its own use-case — geometric mean for rates of growth, harmonic mean for rates like speed) are core. Percentages underlie profit/loss and interest calculations, so fluency here speeds up everything downstream.
Simple interest vs compound interest (and compounding frequency effects), profit & loss (including discount calculations), and the classic trio of time & work, time & distance, and speed & distance problems — all built on the same underlying rate × time = quantity logic, just applied to different contexts.
Mensuration (2D & 3D) covers area/perimeter and volume/surface-area formulas across different shapes. Data interpretation — reading tables, bar charts, pie charts and histograms — tests analysis and sufficiency of given data, often combined with concepts of probability, permutations & combinations, and measures of dispersion (range, standard deviation — how spread out a data set is).
Number/letter series and coding-decoding test pattern recognition. Blood relations and Venn diagrams test relationship-mapping. Clocks & calendars test time-based logical calculation (angle between clock hands, day-of-week calculations). Syllogisms test formal logical deduction from given statements, while statement-assumption and statement-conclusion questions test whether a given inference logically follows. Seating arrangement puzzles (linear/circular) test systematic deduction from multiple constraints.
Some state PSC syllabi additionally test properties of different figures (triangles, circles, polygons) and shape-based sub-sections — geometry-adjacent reasoning rather than pure verbal/numerical logic.
This section rewards practice and speed far more than theory — regular timed drills matter more than reading new concepts close to the exam.
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