suma
111+32=143
diferenta
111-32=79
catul
111:32=3 rest 15
suma lor
143+79+3=225
7*a=56
a=56:7
a=8
7b<56
b<56.7
b<8
b={0,1,2,3,4,5,6,7}
28<7c<56
7c<56
c<8
28<7c
c>4
c={5,6,7}
a:5=7
a=7*5
a=35
b:6<7
b<7*6
b<42
4<c:6<42
c:6<42
c<42:6
c<7
4<c:6
c<6*4
c>24
c={5,6}