LMN Industries intends to purchase a machine to expand its production capacity. Three options are being evaluated. The relevant details including estimated yearly expenditure and sales are as follows. Assume all sales are on cash. The corporate income-tax rate is 33%. Interest on capital may be assumed to be 10%.

Particulars	Machine P(Rs)	Machine Q(Rs)	Machine R(Rs)
Initial investment	3,20,000	3,50,000	3,80,000
Estimated annual sales	5,50,000	5,80,000	6,00,000
Cost of production:
Direct material	60,000	55,000	65,000
Direct labour	50,000	45,000	55,000
Factory overhead	75,000	70,000	80,000
Administration cost	18,000	16,000	20,000
Selling & Distribution cost	10,000	9,000	11,000

The economic life of Machine P is 5 years, Machine Q is 4 years, and Machine R is 6 years. The scrap values are Rs.25,000, Rs.20,000, and Rs.30,000 respectively. Calculate the most profitable investment based on the payback period method.