What is the rate of simple interest at which a sum of money doubles itself in 5 years ?

Explanation

To find the rate of simple interest at which a sum of money doubles itself in 5 years, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Problem**: We need to find the rate of simple interest (R) that allows a principal amount (P) to double in 5 years (T).

2. **Define the Principal**: Let's assume the principal amount (P) is 100 units (this makes calculations easier, but the result will be the same for any principal).

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