GED Math Formula Reference Sheet

📐 Geometry — Area

Rectangle: A = length × width

📋 From the Tutor's Desk:

Do not panic about memorizing the geometry formulas. The GED Math test actually provides you with a formula sheet on screen. I had a student spend three days trying to memorize the surface area of a cone. I told her to stop. Your job isn't to memorize the formula; your job is to know how to plug numbers into it when they hand it to you.

Triangle: A = ½ × base × height

Circle: A = π × r² (π ≈ 3.14)

Parallelogram: A = base × height

Trapezoid: A = ½ × (b₁ + b₂) × height

📏 Perimeter & Circumference

Rectangle: P = 2(l + w)

Triangle: P = a + b + c

Circle: C = 2 × π × r (or π × d)

📦 Volume

Rectangular prism: V = l × w × h

Cylinder: V = π × r² × h

Cone: V = ⅓ × π × r² × h

Sphere: V = ⁴⁄₃ × π × r³

Pyramid: V = ⅓ × base area × h

📊 Statistics

Mean: Sum of values ÷ Number of values

Median: Middle value (sorted)

Mode: Most frequent value

Range: Highest − Lowest

📈 Slope & Linear Equations

y = mx + b

m = slope: (y₂ − y₁) / (x₂ − x₁)

b = y-intercept: where line crosses y-axis

Parallel lines: same slope

Perpendicular: slopes are negative reciprocals

💡 Tutor’s Tip: The GED gives you a formula sheet, but don’t rely on it as a crutch. If you have to look up every formula during the test, you’ll run out of time. Know the top 5 cold (area of rectangle, area of circle, Pythagorean theorem, slope, slope-intercept form).

🔢 Number Properties

Order of operations: PEMDAS

Absolute value: |−5| = 5

Exponents: a^m × a^n = a^(m+n)

Square root: √(a × b) = √a × √b

💯 Percentages & Ratios

% = Part / Whole × 100

% change: (New − Old) / Old × 100

Cross multiply: a/b = c/d → ad = bc

Discount: Price × (1 − discount rate)

Tax: Price × (1 + tax rate)

✖️ Algebra

Distributive: a(b + c) = ab + ac

FOIL: (a+b)(c+d) = ac + ad + bc + bd

Quadratic formula: x = (−b ± √(b²−4ac)) / 2a

Pythagorean theorem: a² + b² = c²

Tip: Common right triangles: 3-4-5, 5-12-13, 8-15-17

🔄 Conversions

Measurement	Equivalence
1 foot	12 inches
1 yard	3 feet
1 mile	5,280 feet
1 gallon	4 quarts
1 quart	2 pints
1 pint	2 cups
1 pound	16 ounces
1 ton	2,000 pounds

📝 GED Math Tips

1. Part 1 = 5 questions, NO calculator

2. Part 2 = TI-30XS available

3. Passing score = 145+

4. ~2.5 min per question in Part 2

5. Estimate before calculating

💡 Tutor’s Tip: GED Math is 45% algebra. If you can solve equations like 2x + 5 = 13, you’ve already conquered nearly half the test. Practice isolating the variable until it’s second nature — do 10 problems every morning.

GED Math Formulas & Reference

📐 Geometry — Area

📏 Perimeter & Circumference

📦 Volume

📊 Statistics

📈 Slope & Linear Equations

🔢 Number Properties

💯 Percentages & Ratios

✖️ Algebra

🔄 Conversions

📝 GED Math Tips

Self-Study Portal — Pass the GED Faster

GED Study Resources