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A man invested a sum of money at compound interest. It amounted to Rs. 2420 in 2 years and to Rs. 2662 in 3 years. Find the sum ?

1Rs. 1000
2Rs. 2000
3Rs. 5082
4Rs. 3000

Answer:- 1

Explanation:-

Solution:

\begin{aligned} R % = \frac{2662 - 2420}{2420} \times 100 \\ = \frac{242}{2420} \times 100 \\ = 10 % \\ 2 years CI % \\ =  10 + 10 + \frac{10 \times 10}{100} \\ = 21 % \\ So, 121 % =  2420 \\ \Rightarrow 100 % =  2000 \end{aligned}

$\eqalign{ & {\text{R}}\% {\text{ = }}\frac{{2662 - 2420}}{{2420}} \times 100 \cr & = \frac{{242}}{{2420}} \times 100 \cr & = 10\% \cr & {\text{2 years CI}}\% \cr & {\text{ = 10 + 10 + }}\frac{{10 \times 10}}{{100}} \cr & = 21\% \cr & {\text{So, 121}}\% {\text{ = 2420}} \cr & \Rightarrow {\text{100}}\% {\text{ = 2000}} \cr}$

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", "dateCreated": "7/24/2019 10:09:12 AM", "author": { "@type": "Person", "name": "Nitin Sir" } }, "suggestedAnswer": { "@type": "Answer", "text": "

Solution:

\begin{aligned} R % = \frac{2662 - 2420}{2420} \times 100 \\ = \frac{242}{2420} \times 100 \\ = 10 % \\ 2 years CI % \\ =  10 + 10 + \frac{10 \times 10}{100} \\ = 21 % \\ So, 121 % =  2420 \\ \Rightarrow 100 % =  2000 \end{aligned}

$\eqalign{ & {\text{R}}\% {\text{ = }}\frac{{2662 - 2420}}{{2420}} \times 100 \cr & = \frac{{242}}{{2420}} \times 100 \cr & = 10\% \cr & {\text{2 years CI}}\% \cr & {\text{ = 10 + 10 + }}\frac{{10 \times 10}}{{100}} \cr & = 21\% \cr & {\text{So, 121}}\% {\text{ = 2420}} \cr & \Rightarrow {\text{100}}\% {\text{ = 2000}} \cr}$ ", "dateCreated": "7/24/2019 10:09:12 AM" } }

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