A pumping set with a motor has been installed in a building at a cost of Rs.2500.00. Assuming the life of the pump as 15 years, work out the amount of annual instalment of sinking fund required to be deposited to accumulate the whole amount of 4% compound interest.

Correct Answer: Rs.125
The annual sinking fund, I = Si / = 2500*0.04/(1+0.04)15-1 = 2500*0.05 = Rs.125 The owner is to deposit Rs.125/- annually in 4% compound interest carrying investment for 15 years to accumulate Rs.2500/-.