Quantitative Aptitude Ques 1620

Question: The compound interest accrued on an amount of Rs. 25500 at the end of three years is Rs. 8440.5. What would be the simple interest accrued on the same amount at the same rate in the same period?

Options:

A) Rs. 4650

B) Rs. 5650

C) Rs. 6650

D) Rs. 7660

E) None of these

Show Answer

Answer:

Correct Answer: D

Solution:

  • [d] Amounts = Rs. (25500 + 8440.5) = Rs. 33940.5 $ A=P{{( 1+\frac{R}{100} )}^{T}} $

$ \therefore $ $ 33940.5=25500{{( 1+\frac{R}{100} )}^{3}} $

$ \Rightarrow $ $ \frac{33940.5}{25500}={{( 1+\frac{R}{100} )}^{3}} $

$ \Rightarrow $ $ \frac{339405}{255000}={{( 1+\frac{R}{100} )}^{3}} $

$ \Rightarrow $ $ \frac{1331}{1000}={{( 1+\frac{R}{100} )}^{3}} $
$ \Rightarrow $ $ {{( \frac{11}{10} )}^{3}}={{( 1+\frac{R}{100} )}^{3}} $

$ \Rightarrow $ $ 1+\frac{R}{100}=\frac{11}{10} $
$ \Rightarrow $ $ \frac{R}{100}=\frac{11}{10}-1=\frac{1}{10} $

$ \Rightarrow $ $ R=100\times \frac{1}{10}=10% $

$ \therefore $ $ SI=\frac{Principal\times Time\times Rate}{100} $ $ =\frac{25500\times 3\times 10}{100}=Rs.,7650 $