0.6∶1.8=x =
5x-x=19.2 30%x+25=40
2.5÷=
4×3.14=
43-4.5=
628÷3.14=
4:0.25=
6÷1.5=
0.42:()3=
( ):9=
40×20%=
32×75%=
6÷30%=
54÷90%=
三五折=( )%
四成五= ( )%
150%÷3=
80%× 60%=
□O□=□,□O□=□
□O□O□=□
□O□=□