2﹣30%= +25%= 4.23﹣23%= ×=
3+= 4×15%= = +50%=
6÷80%= 1.74+7.5= 0.53= 3-3÷4= ×0.4÷×0.4=
2分米:4毫米= 4+ = 3.35+6.65×0= ( ):0.25=1 61×29≈
89 370 10.1×37