magento add tax on custom attribute based price - magento

Question

we sell bunch of product and we need to display each price product and entire box price.For that reason i have created attribute with each price and calling it on product page.So main price of product will be box price and each price will be display from attribute.but now i when i add tax i can see the main price with excluding and including tax but how to apply that tax on attribute based price?
this would be each product price
<?php echo $_product->getResource()->getAttribute('each_price')->getFrontend()- >getValue($_product)?>
this would be whole box price
<?php echo $this->getPriceHtml($_product, true);?>

Answer 1

some thing like this can be done to achive this.please look the code below
<?php $txrate= $_product->getData('tax_percent');
if($txrate!=""):
echo '<div class="each-inc-tax">';
$ech_price= $_product->getResource()->getAttribute('each_price')->getFrontend()->getValue($_product);
$tx=($txrate*$ech_price)/100;
$each_tax=$ech_price+$tx;
echo ' <b>Each Price Including Tax:</b> <b>'. $each_tax.'</b>';
echo '</div>';
endif;

Answer 2

I was using the MSRP attribute in my magento and storing the value excluding Tax, but wishing to display on the frontend including Tax.
I used the following code...
<?php
$_finalPriceExclTax = $this->helper('tax')->getPrice($_product, $_product->getPrice(), false);
$_finalPriceInclTax = $this->helper('tax')->getPrice($_product, $_product->getFinalPrice(), true);
$_taxpercent = $_finalPriceInclTax / $_finalPriceExclTax;
$_msrpPrice = $_product->getMsrp() * $_taxpercent;
?>