Tick (✓) the correct answer:

Question:

Tick (✓) the correct answer:

If the compound interest on a sum for 2 years at $12 \frac{1}{2} \%$ per annum is Rs 510 , the simple interest on the same sum at the same rate for the same period of time is

(a) Rs 400

(b) Rs 450

(c) Rs 460

(d) Rs 480

Solution:

(d) Rs 480

We have : $510=\left\{P \times\left(1+\frac{25}{100 \times 2}\right)^{2}\right\}-P$

$\Rightarrow 510=\Rightarrow\left\{P \times\left(\frac{8+1}{8}\right)^{2}\right\}-P$

$\Rightarrow 510=\left\{P \times\left(\frac{9}{8}\right) \times\left(\frac{9}{8}\right)\right\}-P$

$\Rightarrow 510=\left(\frac{81 \mathrm{P}}{64}-\mathrm{P}\right)$

$\Rightarrow 510=\left(\frac{81 \mathrm{P}-64 \mathrm{P}}{64}\right)$

$\Rightarrow 510=\frac{17 P}{64}$

$\therefore P=\frac{510 \times 64}{17}=$ Rs 1920

Now, SI $=\frac{P \times R \times T}{100}$

$=$ Rs $\frac{1920 \times 2 \times 25}{100 \times 2}=$ Rs 480

 

Leave a comment

Close

Click here to get exam-ready with eSaral

For making your preparation journey smoother of JEE, NEET and Class 8 to 10, grab our app now.

Download Now