Find the principal, if the compound interest compound annually at the rate of 10% per annum for three years is Rs 331.

Explanation

To find the principal amount (P) when the compound interest (CI) is given, we can use the formula for compound interest and the relationship between the principal, the amount, and the interest.

### Step-by-Step Solution:

1. **Understand the given values:**
- Compound Interest (CI) = Rs 331
- Rate of Interest (R) = 10% per annum
- Time (n) = 3 years
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