Gracias por tu pronta ayuda
He realizado lo siguiente pero no me resulta y no se donde esta el horror
<script language="javascript">
function update(id)
{
id = liquida.document.getElementById(id);
cant = liquida.document.getElementById(id).value;
valor = "valor"+id;
total = "total"+id;
valore = liquida.document.getElemenById(valor).value;
totale = 0;
totale.value = cant.value * valore.value;
liquida.document.getElementById(total).value = totale;
}
</script>
<form name="liquida" method="post" action="">
<table width="80%" border="0" cellspacing="0" cellpadding="0">
<tr>
<td>Nombre</td>
<td>Cant</td>
<td>Valor</td>
<td>Total</td>
</tr>
<tr>
<td>Perico</td>
<td><label><input name="1" type="text" id="1" size="8" maxlength="8" onchange="update(this.id)"></label></td>
<td><label><input name="valor1" type="text" id="valor1" size="8" maxlength="8" onchange="update(this.id)"></label></td>
<td><label><input name="total1" type="text" id="total1" size="8" maxlength="8" readonly></label></td>
</tr>
<tr>
<td>Juan</td>
<td><label><input name="2" type="text" id="2" size="8" maxlength="8" onchange="update(this.id)"></label></td>
<td><label><input name="valor2" type="text" id="valor2" size="8" maxlength="8" onchange="update(this.id)"></label></td>
<td><label><input name="total2" type="text" id="total2" size="8" maxlength="8" readonly></label></td>
</tr>
<tr>
<td>Pedro</td>
<td><label><input name="3" type="text" id="3" size="8" maxlength="8" onchange="update(this.id)"></label></td>
<td><label><input name="valor3" type="text" id="valor3" size="8" maxlength="8" onchange="update(this.id)"></label></td>
<td><label><input name="total3" type="text" id="total3" size="8" maxlength="8" readonly></label></td>
</tr>
<tr>
<td>Carlos</td>
<td><label><input name="4" type="text" id="4" size="8" maxlength="8" onchange="update(this.id)"></label></td>
<td><label><input name="valor4" type="text" id="valor4" size="8" maxlength="8" onchange="update(this.id)"></label></td>
<td><label><input name="total4" type="text" id="total4" size="8" maxlength="8" readonly></label></td>
</tr>
</table>
</form>