Copyright by The Goodheart-Willcox Co., Inc.
160
Section 4 Measurement
Square Feet to Square Inches
A square with sides measuring 1′ has an area of one square foot. Since 1′ equals 12″, the ″
square also has an area of 12″ × 12″ or 144 in2. ″
Therefore, to change square feet to square inches, multiply the number of square feet by 144.
1 ft2 = 1
×
144 = 144 in2
Square Inches to Square Feet
To convert square inches to square feet, divide the number of square inches by 144.
1. 144 in2 = 144 ÷ 144 = 1 ft2
2. 1,000 in2 = 1,000 ÷ 144 = 6.9 ft2 (rounded)
3. 3,600 in2 = 3,600 ÷ 144 = 25 ft2
Square Inches to Square Millimeters
A square with sides measuring one inch has an area of one square inch. Since 1″ equals ″
25.4 mm, the square also has an area of 25.4 mm × 25.4 mm or 645.16 square millimeters (mm2).