At the beginning of every year, a man deposited $ 10,000 in a financial institution which paid compound interest at the rate of 20% p.a. He stopped further deposits after three years. The Money remained invested in the financial institution for a further eight years.

Question

At the beginning of every year, a man deposited $ 10,000 in a financial institution which paid compound interest at the rate of 20% p.a. He stopped further deposits after three years. The Money remained invested in the financial institution for a further eight years. 
(a) How much money did he have at the end of the first three years? (4 marks) 
Amount =p (1+ r)^n 
= 10000(1+.2)^3 
=17,280 
(b) How much interest did the money generate in the entire period?  
Amount – interest 
Amount = p (1 + r)^n 
=10000(1.2)^8– 10000 
= 429998.17 – 10000 
=32998.17