Question

At what rate percent per annum will ₹3600 amount to ₹4734 in 3 1/2 years?
Pls answer correctly I will mark you as brainliest pls tomorrow is my test
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Answer 1

$\large\sf\underline{Given:}$

• Principal = Rs 3600

• Amount = Rs 4734

• Time = $\sf\:3 \frac{1}{2}=\frac{7}{2}\:yrs$

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$\large\sf\underline{To\:find:}$

• Rate = ??

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$\large\sf\underline{Solution:}$

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We know ,

$\sf\:Amount=Principal+SI$

$\small{\underline{\boxed{\mathrm\pink{SI=\frac{P×R×T}{100}}}}}$

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Therefore ,

$\sf\: Amount=Principal+\frac{P×R×T}{100}$

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• Let's substitute the given values in the formula :

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$\sf⟹\:4734=3600+[\frac{3600×R×\frac{7}{2}}{100}]$

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$\sf⟹\:4734-3600=\frac{3600×R×\frac{7}{2}}{100}$

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$\sf⟹\:1134=\frac{3600×R×\frac{7}{2}}{100}$

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$\sf⟹\:1134=\frac{36\cancel{00}×R×\frac{7}{2}}{1\cancel{00}}$

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$\sf⟹\:1134=36×R×\frac{7}{2}$

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$\sf⟹\:1134=\frac{252×R}{2}$

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$\sf⟹\:1134×2=252×R$

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$\sf⟹\:2268=252×R$

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$\sf\:oR\:252×R=2268$

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$\sf⟹\:R=\frac{2268}{252}$

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$\sf⟹\:R=\cancel{\frac{2268}{252}}=\cancel{\frac{567}{63}}=\cancel{\frac{81}{9}}=9$

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${\sf{{\purple{⟹\:Rate=9\:percent}}}}$

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!! Hope it helps !!