Basically VAT (Value Added Tax) is a blanket 17.5% added to whatever original price the item is. As it is a nationwide tax it is generally included in virtually everything we buy without us having to add it on. So,
100GBP becomes 117.50GBP after tax. 99.9% of the time the tax is already added to the item by the time we see what the price is so we never actually know what the cost of the VAT is. If any Brits want to work out how much you're paying in VAT on any item simply divide the cost of the item by 1.175, this will give you the pre VAT price. i.e., 50GBP inc vat is 42.55GBP before vat, so you're paying 7.45GBP in tax on every 50GBP you spend.Steve