Hello guys, Whats wrong with this code? My first function working fine but second function is not working. Please help me. Thanks

function bag1()
{
var sum = 0;
var qty = document.form1.qty.value;
var pack = document.form1.pack.value;
document.form1.bag.value = (qty*pack)/100;

}
function bag2()
{
var sum = 0;
var qty = document.form1.qty.value;

var pack1 = document.form1.pack1.value;
document.form1.bag1.value = (qty*pack1)/100;
 }

Here is HTML code

        <input id="item1" name="item1"  type="text" maxlength="255" value=""/> 
        <input   type="text" maxlength="255" value=""/> 
        <input id="weight" name="weight"  type="text" maxlength="255" value=""/> 
        <input id="pack" name="pack"  type="text" maxlength="255" onchange="bag1();" value=""/> 
        <input id="bag" name="bag"  type="text" maxlength="255" value=""/> 
        <input id="rate" name="rate"  type="text" maxlength="255" value=""/>
        <input id="amount" name="amount"  type="text" maxlength="255" value=""/>    
        <input id="element_12" name="type"  type="text" maxlength="255" value=""/>      
        <input id="element_13" name="brand"  type="text" maxlength="255" value=""/> 

<!--------------------------    Caculating 2th Row  --------------------------------------------------------------->                


        <input   type="text" maxlength="255" value=""/> 
        <input   type="text" maxlength="255" value=""/> 
        <input id="weight2" name="weight2"  type="text" maxlength="255" value=""/> 
        <input id="pack2" name="pack2"  type="text" maxlength="255" value=""/> 
        <input id="bag2" name="bag2"  type="text" maxlength="255" onchange="bag2();" value=""/> 
        <input id="rate2" name="rate2"  type="text" maxlength="255" value=""/>
        <input id="amount2" name="amount2"  type="text" maxlength="255" value=""/>  
        <input id="element_12" name="type"  type="text" maxlength="255" value=""/>      
        <input id="element_13" name="brand"  type="text" maxlength="255" value=""/> 
    </form type="submit" value="calculator2">