calcular el > de 3 No

calcular el > de 3 No

program calcul_mayor_de_3;
uses
crt;
var
a,b,c:real;
begin
clrscr;
writeln('dame un mumero');
readln(a);
writeln('dame otro numero');
readln(b);
writeln('dame un numero');
readln(c);
if a>b then
writeln(a)
else
if a>c then
writeln(b);
if a>c then
else
writeln(c);
readkey;

end.