Const
 p=0.515;
Var
 Sum:real;
 i:Byte;

function Nfact(n:LongInt):Extended;
VAR
  i:LongInt;
  fact:Extended;
BEGIN
  IF n=0 THEN fact:=1 ELSE
    BEGIN
      fact:=1;
      FOR i:=1 TO n DO
        fact:=fact*i;
    END;
  Nfact:=fact;
END;

function X2np(X:Extended; n:WORD):Extended;
Var i:WORD;
    Y:Extended;
BEGIN
  IF n=0 THEN X2np:=1 ELSE
  IF n=1 THEN X2np:=X ELSE
  BEGIN
    Y:=X;
    FOR i:=2 TO n DO Y:=Y*X;
    X2np:=Y;
  END;
END;

Function C(m,n:Longint):Extended;
begin
 C:=Nfact(m)/Nfact(n)/Nfact(m-n);
end;

Begin
 Sum:=0;
 For i:=1 to 60 do
  Sum:=Sum+C(100,i)*X2np(p,i)*X2np((1-p),(100-i));
 Writeln('Sum = ',Sum:0:5);
 Readln;
End.