4.09{#blank#}1{#/blank#}4.009    5元{#blank#}2{#/blank#}6.2元        8.1+0.2{#blank#}3{#/blank#}0.2+8.1

0.5{#blank#}4{#/blank#}0.500     6.32m{#blank#}5{#/blank#}6.23m     10-2.7-2.3{#blank#}6{#/blank#}10-(2.7-2.3)

8.03－2.16－3.84=8.03－（{#blank#}1{#/blank#}＋{#blank#}2{#/blank#}）

35.84-(5.84+10.6)             68×168+31×68+68               17.35-(2.17+0.35)-1.83

12.5×5×8×9                  4500÷45÷50

27-12.18-2.82                900÷[3×（48-23）]

72×125                          57×101-57

352-98                                          725+363+75                                        613-168-13

970-790-110                                   203+529                                          489-（216+189）