The flight fare between two cities is increased in the ratio `9:11`. What Is the increase (in Rs.) in the fare, if the original fare was Rs. 18,000?

Options

A. 22000
B. 3600
C. 4000
D. 20000

Answer

To find the increase in the flight fare between two cities when the original fare is Rs. 18,000 and the fare is increased in the ratio of 9:11, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Original Fare and the Ratio**:
- The original fare is given as Rs. 18,000.
- The ratio of the original fare to the new fare is 9:11.

2. **Set Up the Ratio**:
- Let the original fare be represented by 9 parts and the new fare by 11 parts.
- This means if the original fare is 9 parts, the new fare can be expressed as:
\[ \text{New Fare} = \left(\frac{11}{9}\right) \times \text{Original Fare} \]

3. **Calculate the New Fare**:
- Substitute the original fare into the equation:
\[ \text{New Fare} = \left(\frac{11}{9}\right) \times 18000 \]
- Calculate:
\[ \text{New Fare} = \frac{11 \times 18000}{9} = \frac{198000}{9} = 22000 \]

4. **Find the Increase in Fare**:
- The increase in fare can be calculated by subtracting the original fare from the new fare:
\[ \text{Increase} = \text{New Fare} - \text{Original Fare} \]
- Substitute the values:
\[ \text{Increase} = 22000 - 18000 = 4000 \]

5. **Conclusion**:
- The increase in the fare is Rs. 4,000.

### Final Answer:
The increase in the fare is Rs. 4,000.

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