42-6=
23-8=
14-8=
39+4=
43+57=
100-20=
25+36=
65-15=
84-51=
10+56=
14-8= 16-7= 15-8= 18-4=
46+7= 8+64= 58+9= 7+79=
85-9= 63-7= 50-6= 86-50=
13-5+6= 4+7= 19-8-9= 13-7+8=
56-(30-20)= 31+7-10= 63-(30-20)=