[tex]n:28=c \ rest 25 \\\\ n=28c+5 \ \ \ ; \ \ n,c \in N \\\\\\ 100\ \textless \ 28c+5 \ \textless \ 999 \ \ \ |(-5) \\\\ 95\ \textless \ 28c\ \textless \ 995 \ \ \ |:28 \\\\ \frac{95}{28}\ \textless \ c\ \textless \ \frac{995}{28} \\\\\approx 3,39 \ \textless \ c \ \textless \ \approx 35,53 \\\\ \hbox{Pentru cel mai mic numar de 3 cifre c=4, iar pentru cel mai mare c=35} \\\\\\ n=28*4+5 \\\\ n=112+5 \\\\ \boxed{n=117-cel \ mai \ mic} \\\\\\ n=28*35+5 \\\\ n= 980+5 \\\\ \boxed{n=985-cel \ mai \ mare} [/tex]
