Sebastian is self-employed. He drives a ca r with an emission rating of 19 8 g/km and he charges the cost of all the petrol used to his business bank account . In the quarter to 31 July 2017 , he uses his car for both busines s and private journeys but does not keep detailed mileage records. The VAT -inclusive cost of all the petrol bought in the quarter is £798. How should Sebastian deal with petrol in his VAT return for the quarter?