inteleg ca sunt nr de forma adica bara deasupra
1) ab+bc+ca=10a+b+10b+c+10c+a=11a+11b+11c=11(a+b+c)
11(a+b+c)=88 a+b+c=88:11=8
2) 11(a+b+c)=abc a+b+c=abc/11
3)100a+10b+c+100c+10a+b+100b+10c+a=777
111a+111b+111c=777 111(a+b+c)=777 a+b+c=7
4) 10a+b+10a+c+10b+a+10b+c+10c+a+10c+b=110
22a+22b+22c=110 22(a+b+c)=110 a+b+c=110:22=5