Percy has been asked by his manager to perform an analysis of two particular business ventures.

Zeus Electronics, will cost $400,000 today and another $100,000 in one years' time, after which the project is expected to generate income of $100,000 every year.

Percy knows that his company's required rate of return for such projects is 10% per annum effective.

Calculate the Pay Back Period (PBP) for Zeus Electronics

Give your answer rounded to the nearest next whole number.

For example, 10.5 rounded to the nearest next whole number is 11.

10.4 rounded to the nearest to the next whole number is 10.