5 Calculează, pe rând, fracţiile: dau coroana!♡ repedeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee... vă rog.

a) 30:2=15 60:2=30 90:2=45
30:3=10 60:3=20 90:3=30
30:10=3 60:10=6 90:10=9
b) 40:4=10 20:4=5 80:4=20
40:2=20 20:2=10 80:2=40
40:10=4 20:10=2 80:10=8