457+{#blank#}4{#/blank#}=654           {#blank#}5{#/blank#}+261=975        618-{#blank#}6{#/blank#}=256

{#blank#}7{#/blank#}-258=159           246+{#blank#}8{#/blank#}=589         {#blank#}9{#/blank#}+148=742

512-{#blank#}10{#/blank#}=259           {#blank#}11{#/blank#}-201=125         456+{#blank#}12{#/blank#}=545

{#blank#}13{#/blank#}+325=561           641-{#blank#}14{#/blank#}=365         {#blank#}15{#/blank#}-158=369

A＝{#blank#}1{#/blank#}．

①387+546＝

②806﹣318＝

③△914﹣236＝

④272﹣157＝

⑤296+254+357＝

⑥△364+279＝