4)
1/3h=20 min,
1/6h=10 min,
1/60=1 min,
15/60=15 min,
30/60=30 min
1h=60 min
5)
60:2=30, 60:4=15, 60:3=20, 60:5=12, 60:10=6
180:2=90, 180:4=45, 180:3=60, 180:5=36, 180:10=18
480:2=240, 480:4=120, 480:3=160, 480:5=96 480:10=48
840:2=420, 840:4=210, 840:3=280, 840:5=168 840:10=84
6)
1/2=0.5m=0.005km
3/4=0.45m=0.045km
2/5=0.4m=0.004km
3/10=0.3m=0.003km
7)
24x1/4=6ore
24x1/2=12 ore
24x2/6=8 ore
