index.html

<html>
<head>Tea Bags</head>
<body>
	<form  onsubmit="return false" oninput="result.value = 'Total Saving From Extra Teabag Use: ' + calculateSaving(MinsBrewing1Bag.valueAsNumber,
		MinsBrewing2Bag.valueAsNumber,
		Salary.valueAsNumber,
		WorkingDaysInTheYear.valueAsNumber,
		TeaBagPrice.valueAsNumber)">
		Brewing Time with a single teabag (minutes)</br>
		<input name="MinsBrewing1Bag" type="number" placeholder="Mins Brewing (1 Bags)"></br>
		Brewing Time with two teabags (minutes)</br>
		<input name="MinsBrewing2Bag" type="number" placeholder="Mins Brewing (2 Bags)"></br>
		Salary</br>
		<input name="Salary" type="number" placeholder="Salary"></br>
		Working Days in the Year</br>
		<input name="WorkingDaysInTheYear" type="number" placeholder="Working Days"></br>
		Teabag Unit Price</br>
		<input name="TeaBagPrice" type="number" placeholder="Price of a single tea bag"></br>
		</br>
		<output name="result">Enter values in fields above</output>
	</form>
</body>
<script>
	function calculateSaving(minsBrew1, minsBrew2, salary, workDays, teabagPrice) {
		var hourlyWage = (salary / workDays) / 8;
		var minutelyWage = hourlyWage / 60;
		return ((minsBrew1 - minsBrew2) * minutelyWage) - teabagPrice;
	}
</script>
</html>