Approximately what proportion of the global land surface is used for agriculture and grazing by the world's `6` billion people?

Options

A. One eightieth
B. One tenth
C. Three quarters
D. One third

Answer

To solve the question regarding the proportion of the global land surface used for agriculture and grazing by the world's 6 billion people, we can follow these steps:

### Step-by-step Solution:

1. **Understanding Earth's Surface Composition**:
- The Earth's surface is composed of approximately 75% water and 25% land. This means that out of the total surface area of the Earth, only 25% is land.

2. **Dividing the Land Area**:
- Now, we need to focus on the land area. If we take the 25% land area into consideration, we can further divide this land into different uses.

3. **Identifying Agricultural Land**:
- It is commonly estimated that about one-third of the land area is used for agriculture. This includes both crop production and grazing for livestock.

4. **Calculating the Proportion**:
- To find the proportion of the global land surface that is used for agriculture, we take the one-third of the land area (which is 25% of the total surface area).
- Mathematically, this can be expressed as:
\[ \text{Proportion of agricultural land} = \frac{1}{3} \times 25\% = \frac{25\%}{3} \approx 8.33\% \]

5. **Conclusion**:
- Therefore, approximately 8.33% of the global land surface is used for agriculture and grazing.

### Final Answer:
Approximately 8.33% of the global land surface is used for agriculture and grazing by the world's 6 billion people.

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