Find the simple interest on :
a. `₹3500` at `4%` p.a. for `5` years.
b. `₹4300` at `6%` p.a. for `3` years.

Answer

To find the simple interest for the given amounts, we will use the formula for simple interest:

\[ \text{Simple Interest (SI)} = \frac{P \times R \times T}{100} \]

where:
- \( P \) = Principal amount (the initial amount of money)
- \( R \) = Rate of interest per annum (in percentage)
- \( T \) = Time (in years)

### Part a: Find the simple interest on ₹3500 at 4% p.a. for 5 years.

1. **Identify the values**:
- Principal (P) = ₹3500
- Rate (R) = 4%
- Time (T) = 5 years

2. **Substitute the values into the formula**:
\[ SI = \frac{3500 \times 4 \times 5}{100} \]

3. **Calculate the multiplication**:
- First, calculate \( 3500 \times 4 = 14000 \)
- Then, calculate \( 14000 \times 5 = 70000 \)

4. **Divide by 100**:
\[ SI = \frac{70000}{100} = 700 \]

So, the simple interest for part a is **₹700**.

### Part b: Find the simple interest on ₹4300 at 6% p.a. for 3 years.

1. **Identify the values**:
- Principal (P) = ₹4300
- Rate (R) = 6%
- Time (T) = 3 years

2. **Substitute the values into the formula**:
\[ SI = \frac{4300 \times 6 \times 3}{100} \]

3. **Calculate the multiplication**:
- First, calculate \( 4300 \times 6 = 25800 \)
- Then, calculate \( 25800 \times 3 = 77400 \)

4. **Divide by 100**:
\[ SI = \frac{77400}{100} = 774 \]

So, the simple interest for part b is **₹774**.

### Summary of Results:
- Part a: Simple Interest = **₹700**
- Part b: Simple Interest = **₹774**

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