How to calculate this question?

Calculate the Total Cost of Ownership of the following 2 models and determine which model is a better buy. Model X Model Y Purchase price = $50,000 $60,000 Expected useful life = 10 15 Maintenance cost per year = $10,000 $8,000 100 150 Down time per year (number of hours) = Down time cost ($ per hour) = Average mileage per year (km per year) = $50 $50 20,000 20,000 Average fuel costs ($ / litre) = $2 $2 10 8 Fuel efficiency (Litre / 100 km) = Salvage value ($) = $5,000 $2,000