2/7+5/14 = 4/14+5/14 = 9/14
11/15-2/5 = 11/15-6/15 = 5/15=1/3
5/6-1/6 = 4/6=2/3
1/6+3/5 = 5/30+18/30 = 23/30
2/7+1/6 = 12/42+7/42=19/42
7/15+1/15 = 8/15
2/9+7/18 = 4/18 +7/18=11/18
14/21-4/7 = 14/21-12/21 = 2/21
4/15+1/3 = 4/15+5/15=9/15=3/5
2/3-1/3=1/3
4/5+6/25=20/25+6/25=26/25=1,04
11/12-1/12=10/12=5/6
1/2+2/7=7/14+4/14=11/14
13/15-2/3=13/15-10/15=3/15=1/5
3/8+1/3=9/24+8/24=17/24
4/5-1/10=8/10-1/10=7/10=0,7
1/9+2/9=3/9=1/3
5/24-1/6=5/24-4/24=1/24
12/19+7/19=19/19=1
Б.2/7+1/6 = 12/42+7/42=19/42
7/15-1/15 = 6/15=2/5=0,4
2/9+7/18 = 4/18 +7/18=11/18
14/21-4/7 = 14/21-12/21 = 2/21
4/15+1/3 = 4/15+5/15=9/15=3/5
2/3-1/9=6/9-1/9=5/9
4/5+6/25=20/25+6/25=26/25=1,04