Promedio de edades (Mi propuesta)

Buen día a todos!.

<meta charset="UTF-8">
<h1>FAMILY AVERAGE AGES</h1>
<script>
    function saltarLinea() {
        document.write("<br>");    
        document.write("<br>");    
        document.write("<br>" + "<hr>");
        document.write("<br>");    
        document.write("<br>");

    }  
    function imprimir(frase) {
        document.write("<big>" + frase + "</big>");
        saltarLinea();
    }

    var familyMembers = parseInt(prompt("How many members are in the family? "));


    var memberAge = 0;
    var familyAverage = 0;
    var totalAge = 0;
    imprimir("FAMILY AGE AVERAGE");
    for (i=1; i <= familyMembers; i++){
        memberAge = parseInt(prompt("Enter the age of the member # " + i));
        familyAverage = (familyAverage + memberAge)/i;
        totalAge = totalAge + memberAge;
        familyAverage = totalAge/i;
    }
    imprimir("Family average: " + familyAverage);
    imprimir("Game over");




</script>

Espero haber aportado al grupo. Un saludo.