/*

Description:

Write a function that calculates the original product price, without VAT.

Example

If a product price is 200.00 and VAT is 15%, then the final product price (with VAT) is: 200.00 + 15% = 230.00

Thus, if your function receives 230.00 as input, it should return 200.00

Notes:

VAT is always 15% for the purposes of this Kata.

Round the result to 2 decimal places.

If null value given then return -1

*/

function excludingVatPrice(price){

return price===null?-1:Number((price/1.15).toFixed(2));

}