Subtracting a percentage from a number

This calculator subtracts x% from a given number. Imagine that yesterday you wanted to buy a phone for £400, but you didn’t get round to it, and today the same phone is 15% cheaper. This calculator works out the final price of the phone after the discount. Enter 400 in the first field and 15% in the second, and the calculator works out that the phone now costs £340.