You are interested in an investment plan that offers the following returns: For the 1st RM30,000 you invest, you will get a return of 18 percent next year. For the 2nd RM30,000 you invest, you will get a return of 16 percent next year. For the 3rd RM30,000 you invest, you will get a return of 14 percent next year. For the 4th RM30,000 you invest, you will get a return of 12 percent next year. For the 5th RM30,000 you invest, you will get a return of 10 percent next year.

Based on your portfolio, you noticed that you have R150,000 savings deposit. However, you have to pay for a bill to Zaza & co. an amount of RM90,000.

If the current rate of interest is 11 percent p.a., based on the Fishers Theorem how can you optimise your investment and consumption decision?