Certain sum becomes 3 times it self at compound interest in 10 years. In how many years it becomes 9 times
P(1 + R/100)10 = 3P ∴ P(1 + R/100)10 = 3 Let P(1 + R/100)n = 9P ∴ (1 + R/100)n = 9 ∴ 32 = [(1 + R/100)10]2 ∴ (1 + R/100)n => (1 + R/100)20 ∴ n = 20 Years.
What would be the compound interest on Rs.7700/- at 15 ¼% per annum for 2 years compounded annually