Question

Please help me !!!!
~Daca a+b+c=12,calculati abc+bca+cab ( cu linie deasupra cei trei termeni ) .
INDICATIE (data de profa) - abc (cu linie deasupra) = a×100+b×10+c. Dau coronita! :*

Answer 1

a+b+c=12
abc+bca+cab=?
abc = 100a+10b+c 

Dupa ce am descompus in baza zece inlocuim in abc+bca+cab:

100a+10b+c+100b+10c+a+100c+10a+b
 
Adunam toate a-urile, toate b-urile si toate c-urile :

111a+111b+111c

Dam 111 factor comun

111x(a+b+c)=111x12=1332

Answer 2

a+ b+ c=12
___    ___     ___
abc + bca +  cab =?
a·100+b·10+c·1 +b·100+ c·10+ a·1+ c·100+a·10+b·1=
100·(a+b+c)+ 10·(a+b+c)+1·(a+b+c)=
(a+b+c)(100+ 10+  1)=
(a+b+c)·111=
12·111=
1332