47+22= 88-17= 48+35= 13+57= 60+400=
39+23= 78-29= 73-28= 81÷9= 180-90=
26+52= 86-44= 55-25= 17+28= 270+130=
42÷6= 90+50= 24÷3= 80-52= 2000+500=