Math Formulas

 12 inches = 1 foot 3 feet = 1 yard 5,280 feet = 1 mile 1,760 yards = 1 mile   If the dimensions of a rectangle are in inches, multiplying them out will give you the area in square inches. (sq. in.).  If the dimensions are in feet, the area will be in square feet, and so on.   If the dimensions are not in the same measurement, one measurement must be converted.  For example, if the dimensions of a rectangle are 24 inches by 10 feet, you would either multiply 2’ X 10’ to get 20 sq. ft., or you would multiply 24” X 120” to get 2880 square inches.   If the dimensions of a cube (or box) are in inches, the volume would be in cubic inches (cu. in.).  If the dimensions are in feet, the volume would be in cubic feet, and so on. The abbreviation for “inch” or “inches” is “in.”    You may also see the symbol “ The abbreviation for “foot” or “feet” is ft.    You may also see ‘ The abbreviation for “yard” or “yards” is “yd.” The abbreviation for “abbreviation” is “abbrev.”    (In case you were curious.)         144 square inches = 1 square foot 9 square feet = 1 square yard 43,560 square feet = 1 acre   To find square footage on a plot of land, multiply the number of acres by 43,560.  To find the acreage, divide the square footage by 43,560.   27 cubic feet = 1 cubic yard The formula to find the area of a rectangle is Base X Height = Area (B X H = A)   The formula can also be expressed as Length X Width = Area OR Front Footage X Depth = Area   Front footage (also called Frontage) is the distance across the front of the property, and unless you are told otherwise, it will be the dimension given first. The formula to find the area of a triangle is Base X Height divided by 2 = Area   The formula to find the area of a trapezoid is Base One plus Base Two, divided by 2, times the height. The width of a circle (the distance from one side to the other through the center) is the Diameter.   Half the width of a circle (i.e. half of the diameter) is the radius (symbolized by a lower case “r”).   Π = 3.14 (This is the Greek letter, pronounced “Pi,” and may not show up perfectly on every computer – sorry)   To “Square,” is to multiply a number by itself, which is symbolized by a small 2 (or occasionally a box) in the upper right hand corner, for example, 5² would be 5 X 5, or 25 (again, apologies if this doesn’t show up right on your computer) The formula to find the area of a circle is   “Pi” times the radius squared (Π X r²)   In other words, find the radius, multiply that by itself, and then multiply that by 3.14