var x = 5;
var y = 2;
var z = "2";
document.write(x + y); // => `7`
document.write('<br>');
document.write(x + z); // => `52`
document.write('<br>');
document.write(z + "3"); // => `23`
document.write('<br>');
document.write(y + y); // => `4`
document.write('<br>');
document.write(z + z); // => `22`