I had Rs. 10000 with me. Out of this money I lent some money to A for 2 years @ 15% simple interest. I lent the remaining money to B for an equal number of years @18% simple interest. After 2 years, I found that A had given me Rs. 360 more as interest as compared to B. The amount of money which I had lent to B must have been.

1Rs. 2000
2Rs. 3000
3Rs. 4000
4Rs. 5000

Answer:- 1

Explanation:-

Solution:

Let the sum lent to A be Rs. x. and that lent to B be Rs. (10000 - x)
Then,

\begin{aligned} = \frac{x \times 15 \times 2}{100} - \frac{(10000 - x) \times 18 \times 12}{100} = 360 \\ = 30 x - 360000 + 36 x = 36000 \\ \Rightarrow 66 x = 396000 \\ \Rightarrow x = 6000. \end{aligned}

$\eqalign{ & = \frac{{x \times 15 \times 2}}{{100}} - \frac{{\left( {10000 - x} \right) \times 18 \times 12}}{{100}} = 360 \cr & = 30x - 360000 + 36x = 36000 \cr & \Rightarrow 66x = 396000 \cr & \Rightarrow x = 6000. \cr}$
Hence,
Sum lent to B
= Rs. (10000 - 6000)
= Rs. 4000