The compound interest on a certain sum for 2 years at 10% per annum is Rs. 525. The simple interest on the same sum for double the time at half the rate percent per annum is:

– by
Question:
The compound interest on a certain sum for 2 years at 10% per annum is Rs. 525. The simple interest on the same sum for double the time at half the rate percent per annum is:

[A].

Rs. 400

[B].

Rs. 500

[C].

Rs. 600

[D].

Rs. 800

Answer: Option B

Explanation:

Let the sum be Rs. P.

Then, P 1 + 10 2 – P = 525
100
P 11 2 – 1 = 525
10
P = 525 x 100 = 2500.
21

Sum = Rs . 2500.

So, S.I. = Rs. 2500 x 5 x 4 = Rs. 500
100