program pascal;
var f,g:text;
    i,j,n,k,u,aux1,aux2,x:longint;
    max:real;
    sumac,sumat:array[0..30000] of longint;

begin
assign(f,'secv3.in'); reset(f);
assign(g,'secv3.out'); rewrite(g);
readln(f,n,k,u);
for i:=1 to n do
    begin
       read(f,x);
       sumac[i]:=sumac[i-1]+x;
    end;
readln(f);
for i:=1 to n do
       begin
          read(f,x);
          sumat[i]:=sumat[i-1]+x;
       end;


max:=-2000000000;
for i:=1 to n-k+1 do
  begin
    if (sumac[i+k-1]-sumac[i-1])/(sumat[i+k-1]-sumat[i-1])>max then max:=(sumac[i+k-1]-sumac[i-1])/(sumat[i+k-1]-sumat[i-1]);
    for j:=i+k to i+u-1 do
    if j<=n then
      begin
        if (sumac[j]-sumac[i-1])/(sumat[j]-sumat[i-1])>max then  max:=(sumac[j]-sumac[i-1])/(sumat[j]-sumat[i-1]);
      end
    else break;
   end;


write(g,max:0:2);
close(f);
close(g);
end.