Question

The difference between CI and SI on a certain sum of money invested at 20% per annum for 3 years is Rs.1408. Find the sum invested?

Answer 1

Answer:

according to the question

we have,

c.i - s.i = rs. 1408

we know that,

ci = [p(1+r/100)^n -p]

si = prt/100

let the sum be p.

therefore we have,

[p(1+20/100)^3 - p] - p x 20 x 3/100 = 1408

[p(6/5)^3 - p] - 3p/5 = 1408

(216p/125 - p) -3p/5 = 1408

91p/125 - 3p/5 = 1408

16p/125 = 1408

16p = 1408 x 125

p = 1408 x 125/16

p = 88 x 125

p = 11000

the sum invested is RS. 11000