adding and subtracting fraction

1. Adding and subtracting simple
fractions and mixed numbers
without or with regrouping

2. Drill
How do you add/subtract similar fractions with
regrouping?
What can you say about their denominators?
I have here some flashcard. When I flash it to
you solve it on your show me board
d. 9/12 + 4/12
e.. 4 1/10 –2 7/10
f. 4 2/7 –1 5/7
g. 1 11/12 + 2 7/12

3. REVIEW

4. Presentation
• Mrs Martin bought 5 ½ m of white cloth
and 2/5 m of blue cloth . How many
meters of cloth did she buy in all?
We want to know how many meters of cloth
MRS. Martin bought . To solve for the sum of
5 ½ + 2/5 , here are the following steps:

5. • Step 1; Align the fractions and compare
the denominators
5
1
2
+
2
5
Different Denominators

6. Step 2: Find the Least Common
denominator (LCD). Rename the given as
similar fraction.

7. Step 3 ;Add the fractions. Write the whole
number before the fraction sum.

8. Liza is arranging pictures in 2 photo albums.
She has filled 1 2/3 of the albums with
colored and black and white photos of a
picnic at the lake. One-fourth of the filled
pages has black and white photos. What
part of the filled pages has colored photos?

9. Subtract 1/4 and1 2/3
Step 1; Align the fractions and compare the
denominators
1
2
3
-
1
4
Different Denominators

10. Step 2: Find the Least Common denominator
(LCD). Rename the given as similar fraction.

11. Step 3 ; Write the equivalent fractions .

12. Step 4; Subtract the numerator. Write the
difference over the common denominator.

13. In adding and subtracting similar fractions, the
numerators are the only ones being added or subtract.
The sum and difference must be written above the
common denominator. Express the answer in the
simplest form as much as possible.
What if the fractions are dissimilar? How do we add or
subtract dissimilar fractions?
Here are the steps needed in adding and subtracting
fractions and mixed numbers.
1. Convert dissimilar fractions into similar fractions
2. In converting dissimilar fractions to similar fractions,
we need to get the LCD.
3. Add or subtract the whole numbers and the fractional
parts
4. Simplify whenever possible

14. Activity

15. Evaluation
Find the sum/ difference. Express your
answers in lowest terms if needed. Write the
answers on your answer sheets.
1) 2 ½ - 1 2/3
2) 6 2/3 – ¼
3.) 8 3/10 + 2 3/5 + 2 7/12
4) ½ + 2 3/6
5)1/2 +1/3 + ¼

16. Assignment
Find the sum/ difference. Express your
answers in lowest terms if needed.
1. 3¾ + 2 ½ + 3 5/8
2. 13 5/16 – 2 ¾
3. 5 7/8 + 4 7/10 + 3 4/5