Find the SI on Rs 1800 from `21^(st)` Feb. 2003 to `12^(th)` April 2003 at 7.3% rate per annum.

Answer

To find the Simple Interest (SI) on Rs 1800 from 21st February 2003 to 12th April 2003 at a rate of 7.3% per annum, we can follow these steps:

### Step 1: Identify the Principal Amount (P)
The principal amount (P) is given as Rs 1800.

### Step 2: Identify the Rate of Interest (R)
The rate of interest (R) is given as 7.3% per annum.

### Step 3: Calculate the Time Period (T)
We need to calculate the time period from 21st February 2003 to 12th April 2003.

1. **Days remaining in February**:
- February has 28 days in 2003 (a non-leap year).
- Days left in February = 28 - 21 = 7 days.

2. **Days in March**:
- March has 31 days.
- Days in March = 31 days.

3. **Days in April**:
- From 1st April to 12th April = 12 days.

4. **Total Days**:
- Total days = 7 (February) + 31 (March) + 12 (April) = 50 days.

### Step 4: Convert Days to Years
To use the SI formula, we need to convert the time period from days to years.
- Since 1 year = 365 days, we convert 50 days into years:
\[ T = \frac{50}{365} \text{ years} \]

### Step 5: Use the Simple Interest Formula
The formula for Simple Interest is:
\[ SI = \frac{P \times R \times T}{100} \]
Substituting the values:
- P = 1800
- R = 7.3
- T = \frac{50}{365}

So,
\[ SI = \frac{1800 \times 7.3 \times \frac{50}{365}}{100} \]

### Step 6: Calculate the Simple Interest
1. Calculate \(1800 \times 7.3 = 13140\).
2. Now, calculate:
\[ SI = \frac{13140 \times 50}{36500} \]
3. Simplifying:
\[ SI = \frac{657000}{36500} = 18 \]

### Final Answer
The Simple Interest (SI) for the given period is Rs 18.

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