13/14-6/14=7/14
17/20-12/20=5/20=1/4
8/9-1/3=8/9-3/9=5/9
19/24-3/8=19/24-9/24=10/24=5/12
2/3-2/5=10/15-6/15=4/15
1/10-3/100=10/100-3/100=7/100
6+3-2=7 машин стало в мастерской