78－50－9＝{#blank#}1{#/blank#}，72－2－30＝{#blank#}2{#/blank#}

35＋6＋40＝{#blank#}3{#/blank#}，47＋9－20＝{#blank#}4{#/blank#}

17＋3＋15＝{#blank#}5{#/blank#}，75－50＋14＝{#blank#}6{#/blank#}

49－9－30＝{#blank#}7{#/blank#}，28＋20＋2＝{#blank#}8{#/blank#}

99－20＋6＝{#blank#}9{#/blank#}，100－30－7＝{#blank#}10{#/blank#}

16＋15－7＝{#blank#}11{#/blank#}，70－30＋33＝{#blank#}12{#/blank#}

85－6－19＝{#blank#}13{#/blank#}，6＋24＋30＝{#blank#}14{#/blank#}

75－20－30＝{#blank#}15{#/blank#}，62－5＋7＝{#blank#}16{#/blank#}

19-7=      11-3=      20+5=       6+20-6=

4+20=      6+6=      68-8=        8+5+2=

69-9=      40+8=      54-50=      75-5-30=

7×4＝                              5×5＝                              9×4＝                            99－26＝

8×5＝                              9×3＝                              4×4＝                            46＋54＝

15＋40＋15＝                                                     80－17－13＝