Si Ci

To solve the problem, we need to determine the number of years it will take for a sum of money to become five times itself under simple interest, given that it triples in 8 years.

1. Understanding the Concepts:

- Simple Interest (SI): Interest calculated on the original principal for the entire time period.
- Formula:
- Final Amount (A): Given by
- If a sum triples, it becomes , meaning the interest earned is .

2. Given Values:

- in 8 years → SI =
- Using SI formula:

3. Calculate the Rate of Interest:

4. Use Rate to Find Time to Become 5 Times:

To become five times, SI =
Using SI formula:

Final Answer:

The sum will become five times itself in 16 years.