RST Enterprises is evaluating three machines for purchase to meet increasing production demands. The following details are available. Assume all sales are on cash. The corporate income-tax rate is 32%. Interest on capital may be assumed to be 12%.

Particulars	Machine J(Rs)	Machine K(Rs)	Machine L(Rs)
Initial investment	3,50,000	3,80,000	4,00,000
Estimated annual sales	5,00,000	5,50,000	6,00,000
Cost of production:
Direct material	60,000	65,000	70,000
Direct labour	50,000	55,000	60,000
Factory overhead	70,000	75,000	80,000
Administration cost	15,000	18,000	20,000
Selling & Distribution cost	10,000	12,000	15,000

The economic life of Machine J is 4 years, Machine K is 3 years, and Machine L is 5 years. The scrap values are Rs.20,000, Rs.25,000, and Rs.30,000 respectively. Determine the most profitable investment based on the payback period method.