[tex]a+b+c=189 \\ \\ a:b=3 \ rest \ 4 \ <=> a=3b+4 \\ \\ b:c=3 \ rest \ 4 \ <=>b=3c +4 \\ \\ a=3(3c+4)+4 <=> a= 9c+12+4 = 9c+16 \\ \\ 9c+16+3c+4+c=189 \<=>13c +20=189 \\ 13c=189-20 \\ 13c=169 \\ \\ \boxed{c=13} \\ \\ a=9*13+16 \\ a=117+16 \\ \\ \boxed{a=133} \\ \\ b=3*13+4 \\ b=39+4 \\ \\ \boxed{b=43}[/tex]
