When solving measurement problems, sometimes you need to convert, or change, a measurement from one unit to another. When switching between units of measurement, remember these rules:
• Multiply when you are converting from a larger unit to a smaller unit.
• Divide when you are converting from a smaller unit to a larger unit.
Feet and inches are both units of measurement in the U.S. customary system. The symbol for feet is a single vertical dash called a prime (3 ). The symbol for inches is a double prime (3 ). 1 foot is equal to 12 inches.
Example 1: How many total inches are in 2 feet 5 inches?
First, multiply the number of feet by 12.
2 ft × 12 in./ft = 24 inches
Next, add the remaining inches to the total.
24 inches + 5 inches = 29 inches
So 2 feet 5 inches = 29 inches or 29"
Example 2: What is 75 inches in feet and inches?
First, divide the total inches by 12. Make note of the remainder.
75 in. ÷ 12 in./ft = 6 R 3
Next, change the quotient to feet and the remainder to inches. 6 R 3 = 6 feet 3 inches
So 75 inches = 6 feet 3 inches or 6' 3"