Answer:
5/7+3/8=40/56+21/56
=61/56=1/5/56
1/6+5/6=6/6=1
5/6+1/3=5/6+2/6
=7/6=1/1/6
3/4/5+7/1/2=19/5+15/2
=38/10+75/10
=113/10=11/3/10
3/3/4+5/1/3=15/4+16/3
=45/12+64/12
=109/12=9/1/12
2/3-5/8=16/24-10/24
=6/24=1/4
3/7-1/6=18/42-7/42
=11/42
2/3-2/4=8/12-6/12
=2/12=1/6
16/2/3-12/2/5=50/3-62/5
=250/15-186/15
=64/15=4/4/15
7/5/6-3/1/4=47/6-13/4
=94/12-39/12
=55/12=4/7/12