488﹣199=
=
1.25×5×8=
0.16÷0.8=
3.5+2.5= 10﹣0.35= 0.56÷0.7= 20%×5%= 12:2.4=
25×0.8= 9﹣2= 3.75+1= 0÷18= :=
①17+6x=149
②
③0.4x+3.5x=6.24
④x:5=18:15
=