Răspuns:
[tex]2+4+6+.....+abc=abc00\\\\suma.lui-Gauss\\ \\2(1+2+3+.....+abc/2)=abc00\\\\2*[(abc:2+1)*abc/2]:2=abc00\\\\(abc/2+1)*abc/2=abc00\\\\(abc)^2/4+abc/2= abc*100 \\\\abc/4+1/2=100\\ \\ numitor.comun-4 \\ \\ abc+2=400\\\\abc=400-2= > abc=398[/tex]
