1/3+1/6= 1/2+1/3= 3/5-1/10= 1/12+5/6= 1/3+1/4= 1/3+2/5= 1/2-1/4= 8/7-1= 1/4-1/5= 1/2+3/7= заранее

3/6
5/6
5/10
11/12
7/12
11/15
1/4
1/7
1/20
13/14

=2/6+1/6=3/6=1/2
=3/6+2/6=5/6
=6/10-1/10=5/10=1/2
=1/12+10/12=11/12
=4/12+3/12=7/12
=5/15+6/15=11/15
=2/4-1/4=1/4
=8/7-7/7=1/7
=5/20-4/20=1/20
=7/14+6/14=13/14