Question

15. A sum when reckoned at 15/2% per annum amounts to 3920 in 3 years. Find the sum
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Answer 1

Given :

• the sum is reckoned at 15/2% per annum amount in 3 years =3920

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To Find :

• The sum =?

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Formula :

$\red\bigstar\boxed{\sf{ A=P(1+r)^{t} }}$

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Solution :

• Amount =Rs. 3920

•Rate of interest =15/2%

• Time=3years

$\\ \implies\sf{A=P(1+r)^{t}}$

$\\ \implies\sf{3920=P(1+\dfrac{15}{200})^{3}}$

$\\ \implies\sf{\dfrac{3920}{\bigg(1+\dfrac{15}{200} \bigg)^2}=P}$

$\\ \implies\sf{P=\dfrac{3920 \times 64000}{79507}}$

$\\ \implies\sf{P=3155.445 = \approx \: 3155}$

➡ Hence, The sum is Rs. 3155