1. Subtracting Mixed Numbers with Renaming

2. Step 1
Write the problem vertically.
5 ½
- 2 ¾
_________

3. Step 2 Find the LCD for each denominator. Rename ½ to 2/4 and ¾ to ¾.
5 ½ /4
- 2 ¾ ¾
______ ______
Find the LCD of 2 and 4.
2 = 2, 4, 6
4 = 4, 8, 12
The LCD = 4

4. Step 3 Can you subtract the numerators the way they are now? NO!
Rename in order to subtract.

5. Borrow from the 5----make it a 4.
Take away 1 from the whole number 5, and add 1 whole to 2/4.
How do you do this? What is your denominator? 4
What is one whole of 4? 4/4=1 whole
Rename 2/4 to 6/4
5 2/ /4
- 2 ¾ ¾
_______ _______
4 2/4 + 4/4= /4
-2 ¾ ¾
_______ _______

6. Step 4
First subtract the numerators and then you can subtract the whole numbers.
4 6/4
¾ Notice: the bottom mixed number stays the same
______________
2 ¾
What is the difference? 2 ¾

7. Your Turn!
Solve the following word problem using the steps you learned.
It usually takes Mr. Pulley 1 ¾ hours to get to the beach. Due to Independence Day traffic, this summer it took 3 1/3 hours. How much longer did it take this summer?