4÷3=
4
3 ,
5 +
2
5 =
6
5 ,
7 -
7 =0, 4.5×99+4.5=450,
0.72÷0.6=1.2, 1.8×0.5=0.9, 3.1-1.82=1.28, 3.2×4÷3.2×4=16.