Adding and Subtracting Like Fractions

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NAME ______________________________________________ DATE
5-5
____________ PERIOD _____
Adding and Subtracting
Like Fractions (Pages 220–224)
You can add or subtract fractions when they have the same denominators (or
like denominators). When the sum of two fractions is greater than one, you
usually write the sum as a mixed number in simplest form. A mixed
number indicates the sum of a whole number and a fraction.
To add or subtract fractions with like denominators, add or subtract the numerators and write
the sum over the same denominator.
Adding and
Subtracting
Like Fractions
a
b
ab
a
b
ab
and , where c 0.
c
c
c
c
c
c
Examples
2
1
a. Solve r 1 4
.
3
14
30
b. Solve g .
3
r (1 4) 2
3
1
3
15
15
14 30
15
g Add the whole numbers
and fractions separately.
3
3
Subtract the numerators.
16
15
r5 g 3
1
3
r 5 1 or 6
15
15
1
15
1
15
g or 1 Rewrite as a mixed number.
Try These Together
4
1
1. Solve k 6 2
and write
5
3
7
2. Solve n and write
5
10
the solution in simplest form.
10
the solution in simplest form.
Practice
Solve each equation. Write the solution in simplest form.
15
10
3. t
13
10
4. x 9
4
5. r 5
3
6. m 2 1
1
8
7. 2 p
2
1
8. j 4 7
18
18
7
21
7
9
10
16
35
9
21
35
3
16
2
10. w 2 5
9. q 1 16
21
21
3
3
1
11. 1 b
8
8
2
1
1
12. Simplify the expression x x 2
x.
3
3
3
7
13. Standardized Test Practice Evaluate the expression x y for x and
9
1
y .
9
21
4. 12
7
5. 1
7
6. 41
9
7. 12
8. 12
37
3
18
16
9. 11
3
10. 22
2
11. 11
3
12. 31
x 13. B
Glencoe/McGraw-Hill
1
D 9
2. 1 3. 5
©
5
C 3
5
2
B Answers: 1. 43
8
A 9
Glencoe Pre-Algebra
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