(36.8+2.5)+7.5=36.8+(+)
(a+b)×=a×12+×12
7.9+1.1=
3.2÷10=
2.5×100=
0.59+2.41×0=
41.2-10.1=
0.3+4.28=
8-0.2-0.8=
3.4+1.6-3.4+1.6=