Răspuns:
15, 60, 915
Explicație pas cu pas:
[tex]a+b+c=990\\\\4*a=b\Rightarrow b = 4a\\\\c= a+900\\\\inlocuim \:in \:suma\\\\a + 4a + 900 +a = 990\\\\6a + 900 = 990\\\\6a = 990 - 900\\\\6a = 90\\\\a = 90 : 6\Rightarrow \boxed{a=15}\\\\b = 4 * 15 \Rightarrow \boxed{b=60}\\\\c = 15 + 900 \Rightarrow \boxed{c=915}[/tex]
