A contractor can purchase a dump truck for P850, 000 It is estimated that if sold at the end of 7 years it will have a value of P100, 000 Its estimated annual maintenance cost is P12, 000 and daily operating expenses are estimated to be P320 including the wage of the driver It is also possible to hire a similar unit for P1200 a day, including fuel cost If money is worth 10%, how many days a year must the dump truck be used to justify the purchase of the truck