Question

A certain sum of money become 25 times of itself in a span of 50 years on simple interest. Calculate the rate of interest.
1. 45%
2. 28%
3. 32%
4. 50%
5. 48%

Answer 1

Correct Answer - Option 5 : 48%

Given: 

A certain sum of money becomes 25 times of itself in a span of 50 years on simple interest.

Formula:

r = (100 × SI)/(P × t)

SI = A – P

Where, 

SI → Simple interest 

A → Amount 

P → Principal 

r → rate 

t → time

Calculation:

Let the sum of money be P

Amount becomes 25 times = 25P

SI = 25P – P

⇒ 24P

r = (100 × 24P)/(P × 50)

⇒ 2400P/50P

⇒ 2400/50

⇒ 48

∴ The rate of interest is 48%