adding and subtracting unlike denominators

adding unlike denominators

300

5/6+2/5=

7/30

400

5/7+5/9=

17/63

500

5/8+7/9=

67/72

600

7/9+3/4=

29/36

700

7/8+10/12=

17/24

subtracting unlike denominators

300

5/6-2/5=

7/30

400

7/20-8/9=

97/180

500

5/7-7/10=

1/70

600

8/10-5/9=

22/90

700

10/15-8/20=

_16/60

adding and subtracting unlike denominators

300

4/7-5/6=

11/42

400

7/8+4/9=

1 23/72

500

8/9-7/10=

17/90

600

8/10-7/9=

1 52/90

700

4/8-10/18=

4/72

hard adding unlike denominators

300

5/10+6/8=

10 /40

400

10/20+5/25=

70/100

500

10/15+15/20=

25/60

600

8/20+7/24=

60/100

700

 7/20+8/24=

82/120

hard subtracting unlike denominators

300

5/6-7/14=

10/42

400

10/12-5/10=

20/60

500

28/44-1/11=

48/88

600

1/2-3/8=

1/8

700

8/10-7/8=

3/40