On the 1^st of January, a 100,000 investment will be made. For the next 4 years, the cash-flow is expected to be 50,000, 40,000, 60,000 and 75,000 (respectively). Assuming consistent cash inflows throughout each year, what is the expected payback period?

1. 2.2 years

2. 2.1667 years

3. 3 years

4. 2.1 years

5. 2 years