Topic 7 Review

common denominators

100

2/3, 6/12

4/12, 6/12

200

3/9 2/27

21/27, 2/27

300

15/20, 4/5

15/20, 16/20

400

2/9, 3/6

4/18, 9/18

500

9/12, 4/6

9/12, 8/12

Estimate sums and differences of Fractions

100

estimate the fractions then add or subtract:

11/12, 1/4

 

1 + 0 = 1

200

estimate the fractions then add or subtract: 

8/10, 5/10

1 + 1/2 = 1 1/2

300

18/20, 23,30

1 + 1 = 2

400

25/100 30/40

0 + 1 = 1

500

89/100, 23/100

1 + 0 = 1

adding fractions with unlike denominators

100

1/2 + 1/4

4/8 + 2/8 = 6/8

200

1/2 + 2/5 

5/10 + 4/10 = 9/10 

300

7/16+3/8

7/16+6/16 = 13/16

400

4/15 + 9/30

8/30 + 9/30 = 17/30

500

4/50 + 3/5

4/50 + 30/50 = 34/50

Subtract fractions with unlike denominators

100

4/7 - 2/14

8/14 - 2/14 = 6/14

200

5/6 - 2/3

5/6 - 4/6 = 1/6

300

2/3 - 2/7

14/21 - 6/21 = 8/21

400

12/15-1/6

24/30 - 5/30 = 19/30

500

5/4-5/8

10/16 - 10/16 = 0

Add or Subtract Mixed Numbers

100

10 1/3 + 1 7/9

11 1/9

200

7 2/5 - 4 7/10

2 7/10

300

15 1/3 + 1 5/12

16 9/12

400

7 1/4 - 3 5/8

3 5/8 

500

3 7/8 + 5 2/3

9 13/24