Question

If the simple interest on Rs. 1,200 for 4 years and at the same rate of interest simple interest on Rs. 1,600 for 3 years together fetched Rs. 480, then what is the rate of interest per annum?
1. 6.25 percent
2. 5 percent
3. 5.5 percent
4. 6 percent

Answer 1

Correct Answer - Option 2 : 5 percent

Given:

Principle of 4 years is 1,200 at simple interest

Principle of 3 years is 1,600 at simple interest

Total interest get is 480

Formula used:

S.I = (P × R × T)/100

Calculation:

Let the rate of interest be r%

According to the question

(1200 × r × 4)/100 + (1600 × r × 3)/100 = 480

⇒ 48r + 48r = 480 

⇒ r = 480/96 = 5

∴ The rate of interest per annum is 5%