One foot is equal to 12 inches; 36 inches is equivalent to 3 feet in length because 36 divided by 12 is three. Converting measurements from feet to inches (and vice versa) is a simple process using multiplication and division.
When converting from inches to feet, divide the amount of inches by 12 to get the measurement equivalent in feet. When converting from feet to inches, multiply the amount of feet by 12 to get the total measurement in inches. This technique works on any measurement conversion, as long as the conversion factor is known — in this case the conversion factor is 12.