Formula- For finding VAT, when price includes VAT already

$price = 849;  // enter price here

$vat_rate = 20;
$vat = ($price * $vat_rate)/(100+$vat_rate);
echo "\n Price Inc.Vat - > ".$price;
echo "\n VAT - > ".$vat;
$price_ex_vat = $price-$vat;
echo "\n Price Ex. Vat - > ".$price_ex_vat;

Run the above code here:

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