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If the amount received at the end of 2nd and 3rd year at Compound Interest on a certain Principal is Rs 1,800, and Rs 1,926 respectively, w…

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If the amount received at the end of 2nd and 3rd year at Compound Interest on a certain Principal is Rs 1,800, and Rs 1,926 respectively, what is the rate of interest?
  • A7,5%
  • B7%
  • C6%
  • D7%
Answer not set
0
CCommunity
This question was asked some where in previous year papers of ssc, and correct answer was option 2
0
CCommunity
Amount received at the end of 2nd yr $= P(1+\frac{R}{100})^{2} = 1800$ -------(1)

Amount received at the end of 3rd yr $= P(1+\frac{R}{100})^{3} = 1926$ -------(2)

divide (2) with (1)

$\Rightarrow\frac{P(1+\frac{R}{100})^{3}}{P(1+\frac{R}{100})^{2}} = \frac{1926}{1800}$

$\Rightarrow 1+\frac{R}{100} = \frac{1926}{1800}$

$\Rightarrow \frac{R}{100} = \frac{1926}{1800}-1$

$\Rightarrow \frac{R}{100} = \frac{1926-1800}{1800} $

$\Rightarrow \frac{R}{100} = \frac{126}{1800} $

$\Rightarrow \frac{R}{100} = \frac{7}{100} $

$\Rightarrow R = 7%$