Simple & Compound Interest

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Sniper Mode: Money Growth

1. Simple Interest (SI)

  • Formula: SI = (P x R x T) / 100.
  • Amount = P + SI.
  • Concept: SI is same every year.
  • Money Multiplier: Money becomes N times in T years. T = (N-1)*100 / R.

2. Compound Interest (CI)

  • Formula: A = P(1 + R/100)^T.
  • Concept: Interest on Interest. Successive % change.
  • Tree Method (Best): P=1000, 10% Rate.
    • Year 1: 100.
    • Year 2: 100 + 10 (10% of prev interest). Total 210.

3. SI vs CI Difference

  • 2 Years: Diff = P(R/100)^2.
  • 3 Years: Diff = P(R/100)^2 * (300+R)/100.
    • Or use ratio 3:3:1.

4. Installments

  • SI Installment: 100 + (100+R) + (100+2R)... = Total Debt (Due Amount).
    • Watch out: Debt amount includes interest.
  • CI Installment: P = x/(1+R/100) + x/(1+R/100)^2...