Need to multiply a text box value and display in total text box

I have tweaked a JavaScript funtion I borrowed but need to tweak it more and cannot figure it out.  Currently, when a number is entered in one of my textboxes, that number is added to the "total" text box.  I have 6 text boxes.  Here is what I want to happen.  When a number is entered in textbox1, I want it multiplied by 4 and added to the total.  When a number is entered in textbox2, I want it multiplied by 8 and added to the total.  When a number is entered in textbox3, I want it multiplied by 16 and added to the total. Textboxes 4-6 are repeats of Textboxes 1-3. Here are the functions I am using.

function doTotal() {
     var total = 0;
     for (var idx=0;idx<=5;idx++) {
          total += parseFloat(document.getElementById(fldName[idx]).value);
     document.getElementById('txtTotal').value = total;
function calc(f) {
          var idx;
          var costIndex;
          for (idx=0;idx<=5;idx++) {
               if ([idx]) {
                    costIndex = idx;
          for (idx=costIndex;idx<=5;idx++) {
               document.getElementById(fldName[idx]).value = f.value;

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Andrew BeersTechnology LeadCommented:
sort of a odd way to do things but here:

use whatever event you are using if in the input types or on a button:  i'll just call this onEvent="" ok?

<form name="tallyForm">
<input type="text" name="box1" onEvent=" += parseFloat(tallyForm.box1.value) * 4.0>
<input type="text" name="box2" onEvent=" += parseFloat(tallyForm.box2.value) * 8.0>
<input type="text" name="box3" onEvent=" += parseFloat(tallyForm.box3.value) * 16.0>

<input type="text" name="box4" onEvent=" += parseFloat(tallyForm.box4.value) * 4.0>
<input type="text" name="box5" onEvent=" += parseFloat(tallyForm.box5.value) * 8.0>
<input type="text" name="box6" onEvent=" += parseFloat(tallyForm.box6.value) * 16.0>

<input type="text" name="total" value="0">

Doing it this way doesn't require any fancy javascript function... the text boxes handle themselves and then update the total text box from their own event calls.  Like I said I don't know which event you are using but... There's an easy way of doing it... you would refrence them the same way from a standard javascript function too.

Hi Wayne!! it is Xxavier here!! :o)  Give this little ditty a whirl  

function calc(f){
 for (i=1;i<4;i++){

  <p><input type="text" name="box1" onblur=" calc(this.form)">1</p>
  <p><input type="text" name="box2" onblur=" calc(this.form)">2</p>
  <p><input type="text" name="box3" onblur=" calc(this.form)">3</p>
  <p><input type="text" name="box4" onblur=" calc(this.form)">4 </p>
  <p><input type="text" name="box5" onblur=" calc(this.form)">5 </p>
  <p><input type="text" name="box6" onblur=" calc(this.form)">6</p>
  <p><input type="text" name="total" onblur=" calc(this.form)">Total </p>

See ya Xx. :o)

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Andrew BeersTechnology LeadCommented:
I appologize... I had a typo:

<form name="tallyForm">
<input type="text" name="box1" onEvent=" += parseFloat(tallyForm.box1.value) * 4.0;">
<input type="text" name="box2" onEvent=" += parseFloat(tallyForm.box2.value) * 8.0;">
<input type="text" name="box3" onEvent=" += parseFloat(tallyForm.box3.value) * 16.0;">

<input type="text" name="box4" onEvent=" += parseFloat(tallyForm.box4.value) * 4.0;">
<input type="text" name="box5" onEvent=" += parseFloat(tallyForm.box5.value) * 8.0;">
<input type="text" name="box6" onEvent=" += parseFloat(tallyForm.box6.value) * 16.0;">

<input type="text" name="total" value="0">

This method requires no javascript function call nor a overall tally of sums... Although Xx's solution will allow for updated fields and multiple updates rather than a signle update to a box.  Although his version will cause a problem when a text feild has no data AND it needs to be parsed as a float.

waynerayAuthor Commented:
Xxavier's response was what I was looking for.  However, I also like Aqua's response.  Thanks to both of you for your help.
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