Question

At what rate present per annum, the simple interest on₹3,650 will be₹1,314 after 3years?​

Answer 1

Given:

• Principal = Rs. 3650
• Simple Interest = Rs. 1314
• Time = years

What To Find:

We have to find the rate per annum.

Formula Needed:

$\bf SI = \dfrac{P \times R \times T}{100}$

Abbreviations Used:

• SI = Simple Interest
• P = Principal
• T = Time
• R = Rate

Solution:

Using the formula,

$\sf \implies SI = \dfrac{P \times R \times T}{100}$

Substitute the values,

$\sf \implies 1314 = \dfrac{3650 \times R \times 3}{100}$

Multiply the numerator,

$\sf \implies 1314 = \dfrac{10950 \times R}{100}$

Cancel the zeros,

$\sf \implies 1314 = \dfrac{1095 \times R}{10}$

Take 10 to LHS,

$\sf \implies 1314 \times 10 = 1095 \times R$

Multiply the LHS,

$\sf \implies 13140 = 1095 \times R$

Take 1095 to LHS,

$\sf \implies \dfrac{13140}{1095} = R$

Divide 13140 by 1095,

$\sf \implies 12 \: \% = R$

Final Answer:

Therefore, the rate present per annum is 12 %.

Answer 2

☯GIVEN :

• Simple Interest (SI) = Rs 1314

• Principal (P) = Rs 3650

• Time (T) = 3 years

☯TO FIND :

• Rate (R).

☯FORMULA REQUIRED :

• $\bigstar{\underline { \boxed{ \red{ \bf{R = \bigg(\dfrac{SI\times 100}{P \times T} \bigg)\%}}}}}$

➲SOLUTION :

Substituting the given values :

$\implies {\sf{R= \bigg(\dfrac{SI \times 100}{P\times T} \bigg)\% }}$

$\implies {\sf{R = \bigg(\dfrac{ \cancel{1314} \times \cancel{ 100}} { \cancel{3650} \times \cancel{ 3} } \bigg)\%}}$

$\implies {\sf{R = \bigg( 6\times 2 \bigg)\%}}$

$\implies \underline{ \red{ \boxed{\bf{ R=12\%}}}}$

$\huge{\pink{\therefore}}$Rate= 12%.