Compound Interest Ques 18

Question

The simple interest (per annum) accrued on an amount of Rs. 17000 at the end of four years is Rs. 6800. What would be the compound interest (compounded annually) accrued on the same amount at the same rate after two years?

(1) Rs. 3570

(2) Rs. 3260

(3) Rs. 3980

(4) Cannot be determined

(5) Other than those given as options

(IBPS (PO/MT) Pre 2015)

Show Answer

Correct Answer: (1)

Solution: (1)

Given,

P = Rs. 17000, T = 4, and SI = Rs. 6800

$ SI=\frac{P\times R\times T}{100} $

$ \Rightarrow $ $ R=\frac{SI\times 100}{P\times T}=\frac{6800\times 100}{17000\times 4}=10 $

$ CI=P{{( 1+\frac{R}{100} )}^{t}}-P $

$ \therefore $ $ CI=17000{{( 1+\frac{10}{100} )}^{2}}-17000 $

$ =17000{{( \frac{11}{10} )}^{2}}-17000 $

$ =20570-17000$

$=Rs.3570 $