Вычислите сумму:
3/7+1/6+5/14

5/12+2/9+1/18

1/2+1/3+1/9

3/7+1/6+5/14=6/14+5/14+1/6=11/14+1/6=66/84+14/84=80/84=40/42=20/215/12+2/9+1/18=5/12+4/18+1/18=5/12+5/18=15/36+10/36=25/361/2+1/3+1/9=3/6+2/6+1/9=5/6+1/9=30/36+4/36=34/36=17/18