300–150 ={#blank#}1{#/blank#}    300+105 ={#blank#}2{#/blank#}    80+120={#blank#}3{#/blank#}

315–200={#blank#}4{#/blank#}     800–600 ={#blank#}5{#/blank#}    205+50 ={#blank#}6{#/blank#}

5×2+24 ={#blank#}7{#/blank#}    16÷4+20 ={#blank#}8{#/blank#}    35 + 15-40 ={#blank#}9{#/blank#}

2300－300=     450－50=        270＋300=     875＋532=

455＋555=      1200－500=      167＋123=     328－236=

28+23{#blank#}1{#/blank#}64          72-28{#blank#}2{#/blank#}54          460+370{#blank#}3{#/blank#}240+590

62+28{#blank#}4{#/blank#}82+18      26+49{#blank#}5{#/blank#}92-17       15+120{#blank#}6{#/blank#}140-47