Hola a todos!
Comparto mi código, gracias por leer el post y si gustan dejar algún comentario bienvenido.
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Unit 5, Guess</title>
</head>
<body>
    <h1>Guess a number</h1>
    <script>
        function saltarLinea() {
            document.write("<br><br><br><hr><br><br>");      
        }  
        function imprimir(frase) {
            document.write("<big>" + frase + "</big>");
            saltarLinea();
        }   
        alert("Can you guess a number between 0 and 10?");
        var numeroPensado = Math.round(Math.random() * 10);
        var numeroLanzado = parseFloat(prompt("Try it! Put your number"));
        alert("Let's see if you have guess right.");
        if (numeroPensado == numeroLanzado){
            imprimir("YOU ARE RIGHT! previously we have choosen the number: " + numeroPensado + "," + " and yours is: " + numeroLanzado);
        }
        if (numeroPensado != numeroLanzado){
            imprimir("You are wrong! I am sorry, the right number was: " + numeroPensado + "," + " and yours is: " + numeroLanzado);
        }
    </script>   
</body>
</html>