Question

A bank pays RS .240 as interest for 2 years for a sum of Rs 3000 deposited as savings find the rate of interest

Answer 1

Given :

• Simple Interest (SI) → Rs. 240

• Time (t) = 2 years

• Principal (P) = Rs. 3000

To calculate:

• Rate of interest (R)

Calculation:

Here, we'll apply the formula of the simple interest as a suitable equation to find the value of rate of interest (or unknown variable).

As we know that,

★ $\boxed {\sf \purple { SI = \dfrac{PRT}{100} }}$

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Step 1 : Substituting the values we are given.

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$\sf { \dashrightarrow 240 = \dfrac{3000 \times R \times 2 }{100} }$

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Step 2 : Cancelling 2 in numerator and 100 in denominator by 2.

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$\sf { \dashrightarrow 240 = \dfrac{3000 \times R \times 1}{50} }$

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Step 3 : Performing multiplication.

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$\sf { \dashrightarrow 240 = \dfrac{3000R}{50} }$

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Step 4 : Cancelling numerator and denominator in RHS by 50.

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$\sf { \dashrightarrow 240 = 60R }$

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Step 5 : Transposing 60 from RHS to LHS.

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$\sf { \dashrightarrow \dfrac{240}{60} = R }$

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Step 6 : Performing division.

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$\boxed{ \sf \orange { \dashrightarrow 4 \: \% = R }}$

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$\sf {\dag \:Hence, }$

$\boxed{\sf \purple { Rate \: of \: interest = 4 \: \% }}$

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Some more information :

• Principal is also called sum.
• ★ Amount = Principal + Interest

★ $\boxed {\sf \purple { P = \dfrac{100 \times SI}{R \times T} }}$

★ $\boxed {\sf \purple { R = \dfrac{100 \times SI}{P \times T} }}$

★ $\boxed {\sf \purple { T = \dfrac{100 \times SI}{P \times R} }}$