# What will be the Sum? If

The certain sum will amount to ₹ 12,100 in 2 years at 10% per annum of compound interest, interest being compounded annually. The sum is:

- ₹ 10,000
- ₹ 8,000
- ₹ 6,000
- ₹ 12,000

**Answer : (1) Rs. 10, 000
Explanation:-
Given-
**Amount = Rs. 12,100, Time = 2 years, Rate = 10 %, Principal = ?

**Formula-**

**Compound Interest = P [(1 + R/100)**

^{t}

**– 1]**

**Where, P = principal, R = rate, t = time.**

Then, 12,100 = P (1 + 10/100)^{2}

12,100 = P (11/10)^{2}

12,100 = P x 11 x 11/10 x 10

P = 12,100 x 10 x 10/11 x 11

P = 10,000

Then, the principal is Rs. 10,000.