Question

বিদ্যালয় শিক্ষা দপ্তর, পশ্চিমবুঙ্গ সরকার If the amount of Rs 360 in 3 years is Rs 511.2 what will be the amount of Rs 700 in 5 year

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Answer 1

Correct Question

If the amount of ₹360 in 3 years becomes ₹511.2. What will be the amount of ₹700 in 5 years at the same rate of interest?

Answer

First, we should find the simple interest of first statement.

Simple interest :

$\sf \dashrightarrow Total \: Amount - Principle$

$\sf \dashrightarrow 511.2 - 360$

$\dashrightarrow$₹$\sf 151.2$

Now, we should find the rate of interest.

Rate of interest :

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

$\sf \dashrightarrow 151.2 = \dfrac{360 \times R \times 3}{100}$

$\sf \dashrightarrow 151.2 = \dfrac{18 \times R \times 3}{5}$

$\sf \dashrightarrow 151.2 = \dfrac{54 \times R}{5}$

$\sf \dashrightarrow 151.2 = \dfrac{54R}{5}$

$\sf \dashrightarrow R = \dfrac{151.2 \times 5}{54}$

$\sf \dashrightarrow R = \dfrac{756}{54}$

$\sf \dashrightarrow R = 14\%$

Now, we can find the total amount of the second statement. But, first we should find the simple interest.

Simple interest :

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

$\sf \dashrightarrow \dfrac{700 \times 14 \times 5}{100}$

$\sf \dashrightarrow \dfrac{700 \times 14 \times 1}{20}$

$\sf \dashrightarrow \cancel \dfrac{9800}{20} = 490$

Now, we can find the total amount.

Total Amount :

$\sf \dashrightarrow Simple \: Interest + Principle$

$\sf \dashrightarrow 490 + 700$

$\dashrightarrow$₹$\sf 1190$

Hence, the total amount is ₹1190.