How old are you?

link: https://code.sololearn.com/WPljm01Z9jZS/#js 

var promptName = prompt("Whats your Name?");

var promptAge = prompt("How old are you?");

function person(){

    this.name = promptName;

    this.age = promptAge;

    this.birth = gelenYear;

}

function gelenYear(){

    return 2016 - this.age;

}

var p1 = new person();

document.write("Your name is " + p1.name + " and your birth year is "