①2x+3×0.9=24.7
②x+x=15
③=0.7:3.5
= = = =
0.25= 0.76÷0.4= 1.6×12%= 1﹣4÷8=
3.14×11= 5.06+1.2= 0.9×99+0.9= =
989998 3个0.130个百分之一
3.7×1.0 10.9×3.7 n÷0.9(n>0)