UVW Tech wants to invest in new machinery to improve its production line. Three machines are being considered. The relevant details are as follows. Assume all sales are on cash. The corporate income-tax rate is 28%. Interest on capital may be assumed to be 7%.

Particulars	Machine M(Rs)	Machine N(Rs)	Machine O(Rs)
Initial investment	2,80,000	3,00,000	3,50,000
Estimated annual sales	4,50,000	4,80,000	5,00,000
Cost of production:
Direct material	55,000	60,000	65,000
Direct labour	45,000	50,000	55,000
Factory overhead	65,000	70,000	75,000
Administration cost	18,000	20,000	22,000
Selling & Distribution cost	10,000	12,000	14,000

The economic life of Machine M is 3 years, Machine N is 4 years, and Machine O is 5 years. The scrap values are Rs.15,000, Rs.20,000, and Rs.25,000 respectively. Calculate the most profitable investment based on the payback period method