A certain sum amounts to Rs. 4800 in 4 years and to Rs. 5250 in 5 years at simple interst. Find the interest for 2 years.

Answer

To solve the problem step by step, we need to find the simple interest for 2 years based on the information provided.

### Step 1: Understand the given information
We know that:
- The amount after 4 years is Rs. 4800.
- The amount after 5 years is Rs. 5250.

### Step 2: Calculate the interest for 1 year
To find the interest for 1 year, we can subtract the amount after 4 years from the amount after 5 years:

\[ \text{Interest for 1 year} = \text{Amount after 5 years} - \text{Amount after 4 years} \]

Substituting the values:

\[ \text{Interest for 1 year} = 5250 - 4800 = 450 \text{ Rs.} \]

### Step 3: Calculate the interest for 2 years
Now that we have the interest for 1 year, we can calculate the interest for 2 years by multiplying the interest for 1 year by 2:

\[ \text{Interest for 2 years} = \text{Interest for 1 year} \times 2 \]

Substituting the value we found:

\[ \text{Interest for 2 years} = 450 \times 2 = 900 \text{ Rs.} \]

### Final Answer
The interest for 2 years is Rs. 900.

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