Chandu invested Rs 1500 in a scheme offering 10% SI. After 2 years he invested a part of amount he received again in the same scheme for 3 years from which he received Rs 300. Find the amount he did not invest again.

Options

A. Rs. 850
B. Rs. 1000
C. Rs. 950
D. Rs. 800

Answer

To solve the problem step by step, we will follow the process of calculating the simple interest and determining the amount Chandu did not reinvest.

### Step 1: Calculate the Simple Interest for the First Investment
Chandu invested Rs 1500 at a rate of 10% for 2 years. We will use the formula for Simple Interest (SI):

\[ SI = \frac{P \times R \times T}{100} \]

Where:
- \( P \) = Principal amount (Rs 1500)
- \( R \) = Rate of interest (10%)
- \( T \) = Time (2 years)

Substituting the values:

\[ SI = \frac{1500 \times 10 \times 2}{100} = \frac{15000}{100} = 150 \]

### Step 2: Calculate the Total Amount After 2 Years
The total amount (A) after 2 years is the sum of the principal and the interest earned.

\[ A = P + SI = 1500 + 300 = 1800 \]

### Step 3: Determine the Amount Invested Again
Chandu invested a part of the amount he received (Rs 1800) again in the same scheme for 3 years, and he received Rs 300 as interest from this investment.

We will use the SI formula again to find out how much he invested this time.

Let \( P' \) be the principal amount he invested again. The interest earned from this investment is given as Rs 300.

Using the SI formula:

\[ 300 = \frac{P' \times 10 \times 3}{100} \]

### Step 4: Solve for the Principal Amount Invested Again
Rearranging the equation to find \( P' \):

\[ 300 = \frac{P' \times 30}{100} \]

Multiplying both sides by 100:

\[ 30000 = P' \times 30 \]

Now, divide by 30:

\[ P' = \frac{30000}{30} = 1000 \]

### Step 5: Calculate the Amount Not Invested Again
Now we know that Chandu invested Rs 1000 again. To find the amount he did not invest again, we subtract the amount he reinvested from the total amount he had after 2 years.

\[ \text{Amount not invested again} = 1800 - 1000 = 800 \]

### Final Answer
The amount Chandu did not invest again is **Rs 800**.

---