InterviewSolution
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The compound interest on a certain sum for 2 years is Rs. 900 and the simple interest is Rs. 800. The difference between compound and simple interest for 3 years is?1). Rs. 4002). Rs. 5003). Rs. 7754). Rs. 325 |
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Answer» The difference between C.I. and S.I. for 2 YEARS = S.I. on the INTEREST of first year ⇒ S.I. for first year = RS. 400 ⇒ The S.I. on interest of first year = C.I. – S.I. = 900 – 800 = Rs. 100 ⇒ Interest on Rs.400 for 1 year = Rs. 100 ⇒ Interest on Rs.100 for 1 year = x ⇒ i.e, x = [(100 × 100)/400] = Rs. 25 ⇒ Thus the rate of interest = 25% $(\Rightarrow {\rm{Principal\;AMOUNT}} = {\rm{}}\frac{{\left( {100 \times {\rm{S}}.{\rm{I}}} \right){\rm{\;}}}}{{RT}})$ ⇒ Principal amount = (100 × 800)/(2 × 25) ⇒ Principal amount = Rs. 1600 ⇒ S.I. for 3 years = (1600 × 3 × 25)/100 ⇒ S.I. for 3 years = Rs. 1200 ⇒ C.I. for 3 years = 1600[(1 + 0.25) 3 – 1] ⇒ C.I. for 3 years = Rs. 1525 ⇒ Difference between C.I. and S.I. for 3 years = 1525 – 1200 = Rs. 325 ∴ Difference between C.I. and S.I. for 3 years = Rs. 325 |
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