57.6÷100= 25×8= 3.02×10= 45n-29n=
6.72+1.09= 1-0.78= 8.8+2.12= 7-925÷1000=
17.49+6.3= 20.6-16.8=
①67.73+39.67= ②★59-28.19=
7元零8分﹣3元9角
3km50m+750m
10kg﹣2kg650g