General Studies and Analytical Ability (Reasoning, Quantitative Aptitude, Data Interpretation)
General Studies and Analytical Ability tests reasoning, quantitative aptitude and data interpretation. The goal is accuracy under time pressure: classify the problem, write the governing equation, and avoid unnecessary calculation.
Quantitative
Percentages, ratio–proportion, averages, time–speed–distance, time–work, interest and mensuration. Use fractions for repeated percentage changes: successive 20% and 10% increases give 1.2 × 1.1 = 1.32, i.e. 32%.
Reasoning
For syllogisms, draw minimal Venn diagrams; for seating, fix one anchor and branch; for coding–decoding, test letter positions. Blood relations are best solved with a family tree.
Data interpretation
Read titles, units, base years and whether values are absolute or percentage. In tables, compare ratios rather than raw differences when totals differ.
Worked example
A can finish work in 12 days, B in 18. Together, one day’s work = 1/12 + 1/18 = 3/36 + 2/36 = 5/36. Time = 36/5 = 7.2 days. If A works alone for 3 days first, remaining work = 1 − 3/12 = 0.75; B alone takes 0.75 × 18 = 13.5 days, so total = 16.5 days.
Traps
Confusing percentage and percentage points; using simple average on rates; forgetting unit conversions, including km/h to m/s by multiplying by 5/18; and over-reading a graph whose axis does not start at zero.