Comparing Quantities

• Introduction to Comparing Quantities
  • Concept of Ratio
    • Comparison by division
    • Must be in the same units
    • Equivalent ratios
  • Concept of Proportion
    • Equality of two ratios
    • Product of extremes = Product of means
• Percentage
  • Meaning of percentage (per hundred)
  • Converting Fractions/Decimals to Percentages
  • Converting Percentages to Fractions/Decimals
  • Finding a percentage of a given quantity
  • Converting ratios to percentages
  • Increase or Decrease as a Percentage
• Use of Percentages
  • Interpretation of percentages in daily life
  • Finding Cost Price (CP) and Selling Price (SP)
    • Profit = $SP - CP$ (when $SP > CP$)
    • Loss = $CP - SP$ (when $CP > SP$)
    • Profit or Loss Percentage formula
• Simple Interest (SI)
  • Key Components
    • Principal ($P$): Initial amount
    • Rate ($R$): Percentage per year
    • Time ($T$): Duration in years
    • Amount ($A$): $P + SI$
  • Formula
    • $SI = \frac{P \times R \times T}{100}$