Basic math formulas

Find here a comprehensive list of basic math formulas commonly used when doing basic math computation

Average formula:

Let a1,a2,a3,......,an be a set of numbers, average = (a1 + a2 + a3,+......+ an)/n

Fractions formulas:

Converting an improper fraction to a mixed number:

Formula for a proportion:

In a proportion, the product of the extremes (ad) equal the product of the means(bc),

Thus, ad = bc


Percent to fraction: x% = x/100

Percentage formula: Rate/100 = Percentage/base

Rate: The percent.
Base: The amount you are taking the percent of.
Percentage: The answer obtained by multiplying the base by the rate

Consumer math formulas:

Discount = list price × discount rate

Sale price = list price − discount

Discount rate = discount ÷ list price

Sales tax = price of item × tax rate

Interest = principal × rate of interest × time

Tips = cost of meals × tip rate

Commission = cost of service × commission rate

Geometry formulas:


Perimeter of a square: s + s + s + s
s:length of one side

Perimeter of a rectangle: l + w + l + w
l: length
w: width

Perimeter of a triangle: a + b + c
a, b, and c: lengths of the 3 sides


Area of a square: s × s
s: length of one side

Area of a rectangle: l × w
l: length
w: width

Area of a triangle: (b × h)/2
b: length of base
h: length of height

Area of a trapezoid: (b1 + b2) × h/2
b1 and b2: parallel sides or the bases
h: length of height


Volume of a cube: s × s × s
s: length of one side

Volume of a box: l × w × h
l: length
w: width
h: height

Volume of a sphere: (4/3) × pi × r3
pi: 3.14
r: radius of sphere

Volume of a triangular prism: area of triangle × Height = (1/2 base × height) × Height
base: length of the base of the triangle
height: height of the triangle
Height: height of the triangular prism

Volume of a cylinder:pi × r2 × Height
pi: 3.14
r: radius of the circle of the base
Height: height of the cylinder

Have any questions about the basic math formulas? Send me an email here and ask me any questions you want about these basic math formulas

Recent Articles

  1. Writing an Algebraic Expression

    Sep 25, 17 09:22 AM

    Writing an algebraic expression when a phrase is given is the goal of this lesson

    Read More

New math lessons

Your email is safe with us. We will only use it to inform you about new math lessons.

            Follow me on Pinterest

Page copy protected against web site content infringement by Copyscape