<!DOCTYPE html>
<html>
<body>

<p>Click the button to check if every element in the array has a value above a specific number.</p>
<p>Minimum age: <input type="number" id="ageToCheck" value="18"></p>
<button onclick="myFunction()">Try it</button>

<p>All ages above minimum? <span id="demo"></span></p>

<script>
var ages = [32, 33, 12, 40];

function checkAdult(age) {
    return age >= document.getElementById("ageToCheck").value;
}

function myFunction() {
    document.getElementById("demo").innerHTML = ages.every(checkAdult);
}
</script>

</body>
</html>