program stock;
type
fxz=array[1..1000] of real;
var
f1,f2:text;
i,j,q,n,v:longint;
p,ls:real;
a:fxz;

begin assign(f1,'stock.in');
      assign(f2,'stock.out');
      reset(f1);rewrite(f2);
      readln(f1,n);
      for i:=1 to n do
      read(f1,a[i]);
      readln(f1);
      readln(f1,v);
      ls:=0;q:=0;
      for i:=1 to n-1 do
      for j:=i+1 to n do begin inc(q);
                               if (a[j]>a[i])and(a[i]<=v) then
                               if trunc(v/a[i])*(a[j]-a[i])>=ls then ls:=trunc(v/a[i])*(a[j]-a[i]);
                          end;
      writeln(f2,ls:0:3);
      p:=0;
      for i:=1 to n-1 do
      for j:=i+1 to n do if (trunc(v/a[i])*(a[j]-a[i])>0)and(a[i]<=v) then p:=p+1/q;
      writeln(f2,p:0:3);
      close(f1);close(f2);
end.