To determine the gradient of the slope X-Y, we need to understand what gradient means in geographical terms. The gradient is a measure of how steep a slope is, typically expressed as a ratio of vertical rise to horizontal run. This is often represented in the form of a ratio, such as 1:24, 1:26, 1:28, or 1:30. Step-by-Step Explanation

1. Understanding Gradient:
2. The gradient is calculated using the formula: [ \text{Gradient} = \frac{\text{Vertical Rise}}{\text{Horizontal Run}} ]
3. This means for every unit of horizontal distance, how much vertical distance is gained.
4. Interpreting the Options:
5. The options given (1:24, 1:26, 1:28, 1:30) indicate the steepness of the slope. A smaller number in the denominator indicates a steeper slope, while a larger number indicates a gentler slope.
6. Calculating the Gradient:
7. To find the correct option, we would typically need specific measurements of the vertical rise and horizontal run. However, since we are given that the correct answer is C (1:28), we can infer that the vertical rise is 1 unit for every 28 units of horizontal distance.
8. Why Option C is Correct:
9. The ratio 1:28 suggests that for every 28 units you move horizontally, you gain 1 unit of elevation. This indicates a relatively gentle slope, which is often found in geographical features like rolling hills or gentle inclines.
10. Why Other Options are Incorrect:
11. Option A (1:24): This indicates a steeper slope than 1:28. If the slope were 1:24, it would mean that for every 24 units of horizontal distance, there is a 1 unit rise, which is steeper than what is indicated by option C.
12. Option B (1:26): Similar to option A, this also represents a steeper slope than 1:28. It suggests that the slope is not as gentle as the correct answer.
13. Option D (1:30): This indicates a gentler slope than 1:28. It would mean that for every 30 units of horizontal distance, there is a 1 unit rise, which is less steep than the correct answer.

Common Pitfalls

• Misinterpreting Ratios: Students often confuse the ratios. Remember, a larger denominator means a gentler slope.
• Not Visualizing the Slope: It can be helpful to visualize or sketch the slope to understand how steep it is.
• Assuming Without Calculation: Always calculate or analyze the given data before jumping to conclusions.

Revision Summary

• The gradient is the ratio of vertical rise to horizontal run.
• A smaller denominator indicates a steeper slope, while a larger one indicates a gentler slope.
• The correct answer is C (1:28), indicating a gentle slope.
• Always visualize slopes and carefully analyze ratios to avoid confusion.

By understanding these concepts, you can confidently tackle questions related to gradients and slopes in geography.