Question

how many years will it take for a sum of monday to double at a simple interest rate of 5%​

Answer 1

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• how many years will it take for a sum of money to double at a simple interest rate of 5%

$\sf{\bold{\green{\underline{\underline{Given}}}}}$

• Amount = 2 × Principle
• Rate = 5%

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$\sf{\bold{\green{\underline{\underline{To\:Find}}}}}$

• Time = ??

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$\sf{\bold{\green{\underline{\underline{Solution}}}}}$

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• Let the sum or principle be x

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Amount = 2 × Principle

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Amount = 2x

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$\sf{\red{\boxed{\bold{Interest = Amount - Principle}}}}$

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Interest = 2x - x

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Interest = x

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$\sf{\red{\boxed{\bold{SI = \dfrac{p\times r\times t}{100}}}}}$

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$\sf: \implies\: {\bold{ x = \dfrac{x\times 5\times T}{100}}}$

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$\sf: \implies\: {\bold{ x = \dfrac{x\times T}{20}}}$

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$\sf: \implies\: {\bold{ \dfrac{x\times 20}{x} = T }}$

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$\sf: \implies\: {\bold{ T = 20 years }}$

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$\sf{\bold{\green{\underline{\underline{Answer}}}}}$

• Sum will get double at 5% per annum in 20 years