80cm2=dm2 3m75cm=m
1=0.1 4.005kg= kgg
4.2÷10= 12-8÷4= 3.54×10= 52+8=
2.15×100= 0.25×1000= 2÷100= (15+15) ÷3=
①3500÷14÷5
②48×125
③355+260+140+245
④3×59+3
⑤98×101
⑥172-27-72