Răspuns :
[tex]\it a=2\cdot10^n+61=2\underbrace{000...0}_{n\ zerouri}+61=2\underbrace{000...0}_{n-2\ zerouri}61\\ \\ Suma\ cifrelor\ lui\ a\ este:\\ \\ 2+6+1=9\ \vdots\ 9 \Rightarrow\ a\ \vdots\ 9[/tex]
[tex]\it a=2\cdot10^n+61=2\underbrace{000...0}_{n\ zerouri}+61=2\underbrace{000...0}_{n-2\ zerouri}61\\ \\ Suma\ cifrelor\ lui\ a\ este:\\ \\ 2+6+1=9\ \vdots\ 9 \Rightarrow\ a\ \vdots\ 9[/tex]