var a = 40;
var b = 10;
var tambah = a + b;
var kurang = a - b;
var kali = a * b;
var bagi = a / b;
var mod = a % b;
document.getElementById("tambah").innerHTML = tambah;
document.getElementById("kurang").innerHTML = kurang;
document.getElementById("kali").innerHTML = kali;
document.getElementById("bagi").innerHTML = bagi;
document.getElementById("mod").innerHTML = mod;