Common Math Formulas for Everyday Calculations
This reference guide covers the most commonly needed math formulas for everyday calculations.
Percentage Formulas
X% of Y = Y × (X/100). Percentage change = ((New−Old)/Old) × 100. Discount price = Price × (1 − Discount/100). Margin = ((Sell−Cost)/Sell) × 100. Markup = ((Sell−Cost)/Cost) × 100.
Area & Volume
Rectangle area = L × W. Circle area = π × r². Triangle area = ½ × base × height. Rectangular volume = L × W × H. Cylinder volume = π × r² × h.
Speed, Distance, Time
Speed = Distance / Time. Distance = Speed × Time. Time = Distance / Speed. Remember to use consistent units (km and km/h, or miles and mph).