Adding

1

dding
ubtracting
ractions
2
We need a common denominator to add these
fractions.

3
Count by 2's
2, 4, 6, 8, 10, 12, 14, 16, 18, 20
Count by 7's
7, 14, 21, 28, 35
4
Count by 2's
2, 4, 6, 8, 10, 12, 14, 16, 18, 20
Count by 7's
7, 14, 21, 28, 35
The first number IN COMMON that appears on both
lists becomes the common denominator
LCM least common multiple!
5
x 7
7
Make equivalent fractions.

X 7
x 2
6
Add the numerators


7 6 13
x 2
13
6
Count by 7's
7, 14, 21, 28, 35, 42, 49, 56, 63
Count by 5's
5, 10, 15, 20, 25, 30, 35, 40, 45
7
x 5
15
Make equivalent fractions.

X 5
x 7
7

Add the numerators

x 7
15 7 22
22
8
Count by 7's
7, 14, 21, 28, 35, 42, 49, 56, 63
Count by 8's
8, 16, 24, 32, 40, 48, 56, 64, 72
9
32
x 8
Make equivalent fractions.

x 8
21
Add the numerators
x 7

32 21 53

x 7
53
10
Try These
A
D
E
B
F
C
11
Try These
A
D
B
E
F
C