Question

                             ____   ___  ___     
Demonstreaza ca nr abc +bca+cab  sunt divide cu 37

Answer 1

abc+bca+cab=100a+10b+c+100b+10c+a+100c+10a+b=111a+111b+111c=111(a+b+c)=37*3(a+b+c) => numerele de forma abc+bca+cab sunt divizibile cu 37.

Answer 2

$abc+bca+cab= \\\\ = 100a+10b+c+100b+10c+a+100c+10a+b= \\\\ = 111a+111b+111c= \\\\ =37(3a+3b+3c) : 37 \ \ \ \ (Trebuiau \ 3 \ puncte)$