Formula Cheat Sheet: GED Math (page 2)
Below are mathematics formulas that you will need for the GED math. For both sections on the GED math, a formula sheet will be provided to the test taker; however, you should be familiar and understand when and how to use the formulas prior to the test.
Square: A = side2
Rectangle: A = length × width
Parallelogram: A = base × height
Triangle: A = × base × height
Trapezoid: A = (base1 + base2) × height
Circle: A = π × radius2; π is approximately equal to 3.14.
Circle: C = π × diameter; π is approximately equal to 3.14.
Distance between Points on a Coordinate Plane
Distance between points: ; (x1,y1) and (x2,y2) are two points on the line.
Distance = rate × time
Measures of Central Tendency
Mean: (x1 + x2 +… + xn – x1) ÷ n, where x's are values for which a mean is desired and n is the total number of values for x
Median: the middle value of an odd number of ordered scores, and halfway between the two middle values of an even number of ordered scores
Square: P = 4 × side
Rectangle: P = 2 × length + 2 × width
Triangle: P = side1 + side2 + side3
a2 + b2 = c2; a and b are legs, and c is the hypotenuse of a right angle.
Simple Interest Formula
Interest = principal × rate × time
Slope of a Line on a Coordinate Plane
Slope of a line: (y2 – y1) ÷ (x2 – x1); (x1, y1) and (x2, y2) are two points on the line.
Total cost = number of units × price per unit
Cube: V = edge3
Rectangular solid: V = length × width × height
Square pyramid: V = × (base edge)2 × height
Cone: V = × π × radius2 × height; π is approximately equal to 3.14.
Cylinder: π × radius2 × height; π is approximately equal to 3.14V = B × h (the area of the base times the height).
Rectangular solid: V = l × w × h
Cylinder: V = π × r2 × h