Question

at what rate percent per annum compounded annually, will rupees 20000 amount to rupees 26620 in 3 years

Answer 1

Amount = P { 1 + r%}ⁿ

⇒ 26620 = 20000[1+r%]³


⇒ 26620/20000=[1+r%]³

⇒ 1331/1000 = [ 1+r%]³

⇒ (11/10)³ = [1+r%]³

⇒ 1+ r% = 11/10

⇒ 100+r = 110

∴ r = 10

∴Rate = 10%