To determine the new scale of a map that has been reduced by half, we need to understand how map scales work and how they change when the size of the map is altered. Step-by-Step Explanation

1. Understanding Map Scale:
2. A map scale of 1:50,000 means that 1 unit of measurement on the map (e.g., 1 cm) represents 50,000 of the same units in reality (e.g., 50,000 cm in the real world).
3. This scale indicates a relatively detailed view of the area, as a smaller denominator (50,000) means that the map covers a smaller area in greater detail.
4. Reducing the Map Size:
5. When we say the map is reduced by half, we are effectively halving the size of the map itself. This means that every measurement on the map will now represent a larger area in reality.
6. If the original scale is 1:50,000, reducing the map size by half means that the same distance on the map now represents twice the distance in reality.
7. Calculating the New Scale:
8. To find the new scale, we need to double the denominator of the original scale.
9. The original scale is 1:50,000. If we reduce the map size by half, we calculate the new scale as follows: [ \text{New Scale} = 1 : (50,000 \times 2) = 1 : 100,000 ]
10. Therefore, the new scale of the map after reduction is 1:100,000.

Evaluating the Options Now, let's look at the provided options:

• A. 1:250,000: This scale indicates that 1 unit on the map represents 250,000 units in reality. This is a larger scale than the original and would imply a much less detailed view, which is incorrect since we are reducing the size of the map.
• B. 1:25,000: This scale indicates that 1 unit on the map represents 25,000 units in reality. This is a smaller scale than the original, suggesting a more detailed view, which is also incorrect since we are increasing the area represented by the same map size.
• C. 1:200,000: This scale indicates that 1 unit on the map represents 200,000 units in reality. This is also a larger scale than the original and does not reflect the reduction in size correctly.
• D. 1:100,000: This is the correct answer. It accurately reflects the doubling of the area represented by the same map size after the reduction.

Summary of Key Points

• A map scale indicates the relationship between a unit on the map and the actual distance it represents.
• Reducing a map by half means that the same distance on the map now represents a larger distance in reality.
• To find the new scale after reduction, double the denominator of the original scale.
• The correct new scale after reducing a 1:50,000 map by half is 1:100,000.

Revision Summary

• A map scale of 1:50,000 means 1 unit on the map equals 50,000 units in reality.
• Reducing the map size by half doubles the scale's denominator.
• The new scale after reduction from 1:50,000 is 1:100,000.
• The correct answer is D: 1:100,000.