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The initial cost of a vehicle is Rs. 3,800/- and the trade in value drops as time passes until it reaches Rs. 600/-. The maintenance costs are as shown below. 5 600 Years 1 2 Year-end Trade 2000 1200 Annual Operating Cost 1600 1900 Annual Maintenance Cost 400 500 3 800 2200 700 4 700 2500 900 2800 1100 When should the machine be replaced