JSFiddle - React, Tailwind, and code Playground
by dav sev
HTML
<!DOCTYPE html>
<html>
<body>
width:
<input type="number" id="width" onkeyup="NumOfRolls()"/>
<hr />
length:
<input type="number" id="length" onkeyup="NumOfRolls()"/>
<p ></p>
<h2>rollsAmmount:</h2>
<p id="rollsAmmount"></p>
<h2>lengthByMeter:</h2>
<p id="lengthByMeter"></p>
<h2>finalPrice:</h2>
<p id="demo"></p>
</body>
</html>
JavaScript
function NumOfRolls() {
var RequstedWidth = document.getElementById("width").value;
var RequstedLength = document.getElementById("length").value;
console.log('RequstedWidth ', RequstedWidth);
var fixedRollWidth = 130;
var rollsAmmount = Math.ceil(RequstedWidth/fixedRollWidth);
var lengthByMeter = RequstedLength/100;
var priceUsdPerSquareMeter = 10;
var finalPrice = rollsAmmount * lengthByMeter * priceUsdPerSquareMeter;
document.getElementById("rollsAmmount").innerHTML =rollsAmmount;
document.getElementById("lengthByMeter").innerHTML = lengthByMeter;
document.getElementById("demo").innerHTML = Math.ceil(finalPrice);
}