Step-by-step explanation:
The pay-back period is calculated by dividing the initial investment by the annual cash inflow:
Initial Investment: R360,000
Annual Cash Inflow: R60,000
Pay-back period = Initial Investment / Annual Cash Inflow
Pay-back period = R360,000 / R60,000
Pay-back period = 6 years
Therefore, the pay-back period for the new machine is 6 years.