17/35+1835=35/35=1
3/20+4/5=3/20+16/20=19/20
4/7+2/9=36/63+14/63=50/63
4/15+13/20=16/60+39/60=55/60=11/12
2)0.83
3)0.3(округление)
4)0.7(округление)
17/35+1835=35/35=1
3/20+4/5=3/20+16/20=19/20
4/7+2/9=36/63+14/63=50/63
4/15+13/20=16/60+39/60=55/60=11/12