Imperial Notation

' = feet

“ = inches

Fractional Notation for Lengths (example) 10’-11 ¼”

Common Decimal Conversions for the Imperial System

1″ = 0.083′
2″ = 0.167′
3″ = 0.250′
4″ = 0.333′
5″ = 0.417’
6″ = 0.500′
7″ = 0.583′
8″ = 0.667′
9″ = 0.750′
10″ = 0.833′
11″ = 0.917′

Order of Operations

1. Parenthesis
2. Exponents
3. Multiplication
4. Division
5. Addition
6. Subtraction

Helpful Equations

2𝝅r = perimeter of a circle

2𝝅r (degree of angle ÷ 360) = length of an arc

a2 + b2 = c2 (pythagorean theorem)

a x b ÷ 2 = area of a right triangle

𝝅r2 = area of a circle

Area of Other Triangles

Create a line in the triangle from the angle opposite the longest side (hypotenuse) to the hypotenuse so that it forms two right triangles. Then use the equation to find the area of each right triangle and add them together.