A lomy owner has his own fuel supply and needs to refill his storage tank. He has just completely
filled the fuel tank of the lorry with 170 litres from empty. He now has 100 litres of fuel left in his
storage tank. With the price of fuel expected to fall soon he only wants to buy enough for the next
fortnight. Normally his regular short daily trips total 300 km and this leaves just 20 litres in the
lorry's fuel tank. He expects to complete three regular days of 300 km journeys each week, but
this could rise to five. Sometimes the total journeys are longer but his daily trips never total more
than 400 km in a day. He never works more than five days in a week. His storage container holds
4000 litres
How much fuel should he order to be certain that he has enough for the next two weeks?