Jordan measures a bookshelf and finds it is 3 feet tall. How many inches tall is the bookshelf?
A15 inches — because 3 + 12 = 15
B36 inches — because 3 × 12 = 36
C4 inches — because you add 1 to 3
D3 inches — feet and inches are the same when the number is small
To convert feet to inches, multiply by 12 because each foot contains exactly 12 inches. 3 feet × 12 = 36 inches. Option A (adding 12) is a common error — adding 12 only accounts for 1 foot's worth of inches, not all 3 feet. When you go from a larger unit (feet) to a smaller unit (inches), you need more of them, so the number gets bigger. Multiplication is the right operation when converting to smaller units.
Question 2 Multiple Choice
A ribbon is 48 inches long. A student wants to write this length in feet. What should they do?
AMultiply 48 by 12 to get 576 feet
BDivide 48 by 12 to get 4 feet
CSubtract 12 from 48 to get 36 feet
DAdd 12 to 48 to get 60 feet
To convert from inches to feet, divide by 12, because 12 inches make 1 foot. 48 ÷ 12 = 4 feet. Option A reverses the operation — multiplying gives you more of the smaller unit, which goes the wrong direction. When converting from a small unit (inches) to a large unit (feet), the count gets smaller, so you divide. You can always check: 4 feet × 12 = 48 inches confirms the answer is right.
Question 3 True / False
To convert any measurement from feet to inches, you multiply by 12, because each foot is made up of 12 inches.
TTrue
FFalse
Answer: True
This is always correct. Each foot 'unpacks' into 12 individual inches, so you multiply the number of feet by 12 to count all the inches. 1 foot = 12 inches, 2 feet = 24 inches, 5 feet = 60 inches. The same relationship works every time: feet × 12 = inches.
Question 4 True / False
2 feet and 24 inches are different lengths — feet measure longer objects while inches measure shorter ones.
TTrue
FFalse
Answer: False
They are exactly the same length. 2 feet = 2 × 12 = 24 inches. Feet and inches are just different-sized units for measuring the same thing. Choosing to say '2 feet' versus '24 inches' is like choosing to say you have 1 dollar versus 100 cents — the amount is identical, only the unit name changes. A door that is 2 feet wide and a door that is 24 inches wide are the same door.
Question 5 Short Answer
If you know that 1 foot = 12 inches, how would you figure out how many inches are in 5 feet? Explain your thinking step by step.
Think about your answer, then reveal below.
Model answer: Since 1 foot = 12 inches, 5 feet means 5 groups of 12 inches. Multiply: 5 × 12 = 60. So 5 feet = 60 inches.
The key is to think of each foot as a group of 12 inches. If you have 5 feet, you have 5 such groups. To find the total number of inches, you count how many inches are in all 5 groups combined: 5 × 12. You could also add: 12 + 12 + 12 + 12 + 12 = 60. Both approaches work, but multiplication is faster once you know the basic fact. The rule holds for any number of feet: multiply by 12 to convert to inches.