program pascal;
var f,g:text;
    pi,ps,i,j,n,k,u:longint;
    max:real;
    sumac,sumat:int64;
    cost,timp:array[1..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 read(f,cost[i]);
readln(f);
for i:=1 to n do read(f,timp[i]);

max:=-2000000000;
for i:=1 to n-k+1 do
  begin
    sumac:=0;
    sumat:=0;
    for j:=i to i+k-1 do
      begin
          sumac:=sumac+cost[j];
          sumat:=sumat+timp[j];
      end;
    if sumac/sumat>max then max:=sumac/sumat;

    for j:=i+k to i+u-1 do
    if j<=n then
     begin
        sumac:=sumac+cost[j];
        sumat:=sumat+timp[j];
        if sumac/sumat>max then  max:=sumac/sumat;
     end;
   end;

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