A person borrowed Rs. 100 at the rate of 10% per annum, compounded annually for 2 years. The amount he has to pay after 2 years is Rs. 121.

Answer

To solve the problem of calculating the amount a person has to pay after borrowing Rs. 100 at a rate of 10% per annum compounded annually for 2 years, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the given values:**
- Principal (P) = Rs. 100
- Rate of interest (R) = 10% per annum
- Time (T) = 2 years

2. **Use the formula for compound interest:**
The formula to calculate the amount (A) after T years with compound interest is:
\[ A = P \left(1 + \frac{R}{100}\right)^T \]

3. **Substitute the values into the formula:**
\[ A = 100 \left(1 + \frac{10}{100}\right)^2 \]

4. **Calculate the value inside the parentheses:**
\[ 1 + \frac{10}{100} = 1 + 0.10 = 1.10 \]

5. **Raise the result to the power of T (which is 2):**
\[ (1.10)^2 = 1.10 \times 1.10 = 1.21 \]

6. **Multiply by the principal:**
\[ A = 100 \times 1.21 = 121 \]

7. **Conclusion:**
The amount he has to pay after 2 years is Rs. 121.

### Final Answer:
The amount to be paid after 2 years is Rs. 121.

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