The simple interest accrued in 3 yr on a principal of Rs 25000 is three-twentieth the principal. What is the rate of simple interest percent per annum?

Options

A. 5
B. 4
C. 6
D. 3

Answer

To find the rate of simple interest percent per annum, we can follow these steps:

### Step 1: Understand the given information
We know that:
- Principal (P) = Rs 25,000
- Time (T) = 3 years
- Simple Interest (SI) = (3/20) of the principal

### Step 2: Calculate the Simple Interest
First, we need to calculate the Simple Interest (SI):
\[ SI = \frac{3}{20} \times 25000 \]
Calculating this:
\[ SI = \frac{3 \times 25000}{20} = \frac{75000}{20} = 3750 \]

### Step 3: Use the Simple Interest formula
The formula for Simple Interest is:
\[ SI = \frac{P \times R \times T}{100} \]
Where:
- SI = Simple Interest
- P = Principal
- R = Rate of interest per annum
- T = Time in years

### Step 4: Substitute the known values into the formula
We can substitute the values we know into the formula:
\[ 3750 = \frac{25000 \times R \times 3}{100} \]

### Step 5: Simplify the equation
To simplify, first multiply both sides by 100:
\[ 3750 \times 100 = 25000 \times R \times 3 \]
\[ 375000 = 75000R \]

### Step 6: Solve for R
Now, divide both sides by 75000:
\[ R = \frac{375000}{75000} = 5 \]

### Step 7: Conclusion
The rate of simple interest per annum is:
\[ R = 5\% \]