Find the amount and the compound interest on Rs. 160000 for 2 years at 10% per annum, compounded half-yearly.
Present value, P = Rs.160000
Interest rate, R = 10% per annum
Time, n = 2 years
∵ Compounded half-yearly.
∴ Amount (A) = P [1 + (R/2)/100]2n [Where, P = Present value
R = Annual interest rate
n = Time in years]
∴ A = 160000 [1 + (10/2)/100]4
⇒ A = 160000 [1 + 5/100]4
⇒ A = 160000 [1 + 1/20]4
⇒ A = 160000 [21/20]4
⇒ A = 160000 × 21/20 × 21/20 × 21/20 × 21/20
⇒ A = 160000 × 194481/160000
⇒ A = 1 × 194481
⇒ A = 194481
∴ Amount = Rs.8820
∴ Compound interest = Rs.(194481 – 160000) [∵CI = A – P]
= Rs.34481