Help with Javascript for PDF

[alwclimbs]

I need a JavaScript code for a PDF that populates a multiplication problem between two List Boxes

I'm creating a PDF membership contract and I have two list boxes; one that generates a price and one that is a duration period (3 month, 6 Months, etc..) I need the two list boxes to communication with each other to multiply the price with the duration and that number to appear in a text box.

Example: List box 1 says student membership is $25. List Box 2 says 3 Months. When I click the options, the Text Box will produce a number, in this case $75.00.

[Philip M]

Here you are:-

<select id = "list1" onchange = "calc()">
<option value = 0>Select a membership type</option>
<option value = 25>Student</option>
<option value = 50>Full</option>
</select>

<select id = "list2" onchange = "calc()">
<option value = 0>Select a period</option>
<option value = 3>3 months</option>
<option value = 6>6 months</option>
<option value = 12>12 months</option>
</select>

<br>
<input type = "text" id = "result">

<script type = "text/javascript">
function calc() {
document.getElementById("result").value = "";
var a = document.getElementById("list1").value;
var b = document.getElementById("list2").value;
if (a !=0 && b !=0) {
var c = a * b;
document.getElementById("result").value = "$" + c;
}
}

</script>

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