Puducherry PSC tricks & mnemonics — save minutes on exam day

Data Interpretation

• Percentage-Fraction Equivalents — Memorize: 1/8=12.5%, 1/6≈16.67%, 1/9≈11.11%, 1/7≈14.29%. Speeds up pie-chart and bar-graph calculations instantly without long division.
• Average Trick — If new value added equals new average, old average unchanged. If item removed, new average = (old sum - removed value)/(n-1). Saves recalculation time.
• Ratio Comparison Shortcut — Cross-multiply to compare fractions: a/b vs c/d → compare a×d with b×c. Faster than converting to decimals in data sets.

Numerical Aptitude

• Divisibility by 11 — Alternating sum: subtract even-position digits from odd-position digits. If result is 0 or divisible by 11, number is divisible by 11. Example: 121→(1+1)-2=0✓
• Squares Ending in 5 — For n5²: multiply n×(n+1), append 25. Example: 85²→8×9=72, answer=7225. Instant mental calculation.
• Digital Root for 9-Divisibility — Add all digits repeatedly until single digit. If 9, number divisible by 9. Example: 729→7+2+9=18→1+8=9✓
• Calendar Day Formula — Odd days: count remainder÷7. January 1, 2000 was Saturday. Each ordinary year adds 1 odd day; leap adds 2. Quick date-day calculations.
• Multiplication by 11 — For two-digit ab: write a_(a+b)_b. Example: 11×23=2_(2+3)_3=253. Works when middle sum <10; adjust carry if needed.

Logical Reasoning

• Blood Relations Gender Trick — Mother's/Father's side: always opposite gender for siblings (maternal uncle, paternal aunt). Cousin always needs two links. Saves confusion in family trees.
• Clockwise Alphabet — A=1, Z=26; opposite letters sum to 27 (A-Z, B-Y, C-X). For coded reasoning, instantly find complements without counting backward.
• Venn Diagram Formula — Total = A + B + C - (AB + BC + CA) + ABC + None. Memorize for quick 3-set problems in logical grouping questions.

General Aptitude and Reasoning

• Direction-Sense Net Displacement — Track as coordinates: N=+y, S=-y, E=+x, W=-x. Final position = √(x²+y²). Pythagoras solves minimum distance instantly.
• Series Pattern Checklist — Check: +n, ×n, squares, cubes, primes, alternating operations. Apply BODMAS in mixed-operation series. Systematic eliminates guessing.
• Syllogism Venn Method — Draw circles for each statement. "All A→B" means A inside B; "Some" means overlap; "No" means separate. Visual beats abstract logic.

Awards

• Bharat Ratna Before Padma — Remember hierarchy: Bharat Ratna (highest civilian), then Padma Vibhushan, Padma Bhushan, Padma Shri. Only 3 per year for Bharat Ratna (usually).