<label for=”a”>a:</label>
<input type=”number” id=”a”><br><br>
<label for=”b”>b:</label>
<input type=”number” id=”b”><br><br>
<label for=”c”>c:</ label>
<input type=”number” id=”c”><br><br>
<label for=”d”>d:</label>
<input type=”number” id=”d”><br><br>
<button onclick=”calculate()”>Calculate</button><br><br>
Result: <span id=”result”></span>
<script>
function calculate() {
let a = parseFloat(document.getElementById(“a”).value);
let b = parseFloat(document.getElementById(“b”).value);
let c = parseFloat(document.getElementById(“c”).value);
let d = parseFloat(document.getElementById(“d”).value);
let result = \frac{(a + b + c) \cdot d}{12};
document.getElementById(“result”).textContent = result;
}
</script>
