InterviewSolution
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Rs. 3000 amount to Rs. \(5333\frac{1}{3}\) in 10 years at compound interest, what will Rs. 3000 amount to in half that time?1). Rs. 40002). Rs. 39003). Rs. 3166.664). Rs. 3066.66 |
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Answer» Principal = 3000 Amount $(= \;5333\frac{1}{3}\; = \;\frac{{16000}}{3})$ Time = 10 years Let the rate be R% Using the formula for CI $(compound\;interest = principal{\left[ {1 + \frac{{rate}}{{100}}} \right]^{time}} - Principal)$ $(5333\frac{1}{3} = 3000{\left( {1 + \frac{R}{{100}}} \right)^{10}})$ $(\RIGHTARROW \frac{{16000}}{{3 \times 3000}} = {\left( {1 + \frac{R}{{100}}} \right)^{10}})$ $(\Rightarrow \frac{{16}}{9} = {\left( {1 + \frac{R}{{100}}} \right)^{10}})$ Taking square ROOT of the above equation $(\frac{4}{3} = {\left( {1 + \frac{R}{{100}}} \right)^5})$…………………………………….(equation 1) Now for half the time i.e for T = 5 years Let the amount be A Again using the formula for CI $(A = 3000{\left( {1 + \frac{R}{{100}}} \right)^5})$ From equation (1) $(\Rightarrow A = 3000\left( {\frac{4}{3}} \right))$ ⇒ A = 4000 |
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