Question
Mathematics Question on Compound Interest
A firm anticipates an expenditure of ₹10,000 for a new equipment at the end of 5 years from now. How much should the firm deposit at the end of each quarter into a sinking fund earning interest 10% per year compounded quarterly to provide for the purchase?
[Use (1.025)20=1.7]
₹368.55
₹298.40
₹357.14
₹745.03
₹357.14
Solution
The formula for sinking fund payments is:
A=(1+r)n−1S⋅rr
where A is the periodic payment, S is the future value (target amount), r is the interest rate per period, and n is the total number of periods.
Here:
S=10,000,r=0.025(quarterly interest rate),n=20(quarters).
The sinking fund factor is:
0.025(1.025)20−1=0.0251.7−1=0.0250.7=28.
The quarterly deposit is:
A=2810,000=357.14.
Thus, the firm should deposit Rs. 357.14 at the end of each quarter.