Anamika paid ₹4,965  as compound interest on a loan ₹15,000  after 3 years when compounded annually. Suman took a loan of ₹10,000 at the same rate on simple interest. How much interest did suman pay after 3 years?

₹3,000

The Formula that we used here is -

Amount = P$(1 \;+\; \frac{R}{100})^t$

Compound Interest = Amount - Principal

15000 + 4965 = 15000 [ 1 + \(\frac{R}{100}\)]³

19965 = 15000 [ 1 + \(\frac{R}{100}\)]³

\(\frac{1331}{1000}\) = [ 1 + \(\frac{R}{100}\)]³

(\(\frac{11}{10}\))³  = [ 1 + \(\frac{R}{100}\)]³

\(\frac{11}{10}\) = 1 + \(\frac{R}{100}\)

\(\frac{R}{100}\) = \(\frac{1}{10}\)

R = 10%    ( Interest for suman )

ATQ,

Simple interest = \(\frac{P × R × T}{100}\)

= \(\frac{10000 × 10 × 3}{100}\)

= 3000

So, Interest paid by suman = Rs. 3000