1) 3/4+5/7=21/28+20/28=
=41/28=1 13/28
2) 9/14-3/4=18/28-21/28=-3/28
3) 11/12-2/3=11/12-8/12=3/12=
=1/4
4) 7/25+4/10=14/50+20/50=
=34/50=17/25
5) 11/18-5/12=22/36-15/36=
=7/36
6) 13/18+7/15=65/90+42/90=
=107/90=1 17/90
7) 19/24-25/36=57/72-50/72=
=7/72
8) 5/6-3/4+5/24=
=20/24-18/24+5/24=7/24
9) 5/8+11/28-9/14=
=35/56+22/56-36/56=21/56