In how many months will Rs 8,000 yield Rs 2,648 as compound interest at 20% per annum compounded semi-annually?
Half-yearly rate = 10%. Effective CI % = (2648 / 8000) * 100% = 33.1%. 10% compounding gives 33.1% in 3 half-years = 18 months.
✓ Correct Answer: Option A.
In how much time (in years) will Rs 8,000 amount to Rs 9,159.20 at 14% per annum interest compounded half-yearly?
Half-yearly rate = 7%. Interest = 9159.20 - 8000 = 1159.20. Effective CI = (1159.20 / 8000) * 100% = 14.49%. 7 + 7 + (7*7)/100 = 14.49% (2 half-years = 1 year).
✓ Correct Answer: Option A.
In what time will a sum of Rs 1,25,000 amount to Rs 1,48,877 at 12% per annum, if interest is being compounded half-yearly?
Half-yearly rate = 6% = 3/50, ratio = 53/50. $A/P = 148877 / 125000 = (53/50)^3$. Time = 3 half-years = 1.5 years.
✓ Correct Answer: Option D.
In how many months will Rs 24,000 become Rs 27,783 at compound interest at 20% per annum compounded quarterly?
Quarterly rate = 5%. CI = 27783 - 24000 = 3783. Effective CI = (3783 / 24000) * 100% = 15.7625%. 5% for 3 periods = 15.7625%. 3 quarters = 9 months.
✓ Correct Answer: Option B.
A money-lender claims he lends money at simple interest of 8% p.a., but cleverly includes the interest amount in principal every 6 months. The effective rate of interest becomes:
Half-yearly rate = 4%. Effective rate = 4 + 4 + (4*4)/100 = 8.16%.
✓ Correct Answer: Option A.