Question

At what percent annual compound interest rate, a certain sum amounts to its 8 times in 3 years?

1. 125%
2. 75%
3. 50%
4. 100%

Answer 1

Correct Answer - Option 4 : 100%

Given:

Time = 3 years

Concept:

CI = P(1 + r/100)ⁿ

Calculation:

Let, Sum = P

Time = 3 years

Amount = 8P

According to the question,

⇒ 8P = P × (1 + r/100)³

⇒ 8 = (1 + r/100)³

⇒ 2 = 1 + r/100

⇒ r/100 = 1

⇒ r = 100%