History, Ancient and Medieval History
Mauryan Chronology: "CAB" — Chandragupta (322 BCE), Ashoka (268 BCE), Bindusara (between them). Remember CAB for order: Chandragupta founded, Bindusara expanded, Ashoka peak.
Delhi Sultanate Dynasties: "SKTSL" — Slave (1206), Khilji (1290), Tughlaq (1320), Sayyid (1414), Lodi (1451). "Sakte Hain" for sequence memory.
Vijayanagara Rulers: "SSRT" — Sangama, Saluva, Tuluva, Aravidu dynasties in chronological order. Four S-T-based dynasties.
Mughal Succession: "BAHAJS" — Babur, Akbar, Humayun, Akbar, Jahangir, Shah Jahan, Aurangzeb. Wait—correct: "BAHJAS-A" (Babur-Humayun-Akbar-Jahangir-Shah Jahan-Aurangzeb).
Modern History and Freedom Struggle
1857 Revolt Centers: "DKLMB" — Delhi, Kanpur, Lucknow, Meerut, Bareilly. Five major uprising locations in North India.
Gandhi's Movements Timeline: "CNC-SQ" — Champaran (1917), Non-Cooperation (1920), Civil Disobedience (1930), Salt March (within CD), Quit India (1942). Chronological anchor points.
Moderate-Extremist Split Year: "19-07" — 1907 Surat Session split Congress into Moderates and Extremists. Remember as "19-zero-7."
Indian Constitution
Fundamental Rights Articles: "14 to 32" — All six FR categories fall between Articles 14-32. Article 32 itself is the "Right to Constitutional Remedies"—Dr. Ambedkar's "heart and soul."
DPSP Range: "36 to 51" — Directive Principles span Articles 36-51. Remember: DPs come after Rights (higher numbers).
Constitutional Amendment Majorities — Special majority = 2/3 present + 50% total strength. For federal provisions, add ratification by 1/2 states. Two-step process for structure changes.
Quantitative Aptitude and Numerical Skills
Divisibility by 11: Alternating Sum — Subtract alternate digits (1st-2nd+3rd-4th...). If result is 0 or divisible by 11, original number is divisible by 11. E.g., 121: 1-2+1=0 ✓
Percentage-Fraction Quick Conversions — 12.5%=1/8, 16.67%=1/6, 33.33%=1/3, 37.5%=3/8, 62.5%=5/8, 87.5%=7/8. Memorize these eight for speed calculations.
Simple Interest Formula Trap — SI = PRT/100. Many confuse with CI. Remember: SI is LINEAR (straight graph), CI is CURVED (exponential). SI never compounds.
Speed-Distance-Time Triangle — Draw triangle: D on top, S and T at bottom. Cover what you need: D=S×T, S=D/T, T=D/S. Palm trick for quick recall.
Profit % Formula: "Profit on CP" — Profit% = (Profit/CP)×100, NEVER on SP. Loss% same base. MP-discount calculations work backward from marked price.
Compound Interest Shortcut: 2 years — CI for 2 years = SI for 2 years + (SI for 1 year)²/100. Saves time versus full CI formula.