Urban population of the world is
(a) 0.45
(b) 0.39
(c) 0.35
(d) 0.3

Options

A. 0.45
B. 0.39
C. 0.35
D. 0.3

Answer

To solve the question regarding the urban population of the world, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Total Population**:
- The total population of the world is approximately 7.7 billion people.

2. **Identify the Urban Population**:
- Out of the total population, around 4.2 billion people live in urban areas.

3. **Calculate the Urban Population Percentage**:
- To find the percentage of the urban population, we can use the formula:
\[ \text{Urban Population Percentage} = \left( \frac{\text{Urban Population}}{\text{Total Population}} \right) \times 100 \]
- Plugging in the numbers:
\[ \text{Urban Population Percentage} = \left( \frac{4.2 \text{ billion}}{7.7 \text{ billion}} \right) \times 100 \]

4. **Perform the Calculation**:
- First, calculate the fraction:
\[ \frac{4.2}{7.7} \approx 0.545 \]
- Now, convert this to a percentage:
\[ 0.545 \times 100 \approx 54.5\% \]

5. **Convert Percentage to Decimal**:
- To express the percentage as a decimal, we divide by 100:
\[ 54.5\% \approx 0.545 \]

6. **Compare with Given Options**:
- The options provided are:
- (a) 0.45
- (b) 0.39
- (c) 0.35
- (d) 0.3
- The closest option to our calculation of 0.545 is 0.45.

7. **Select the Correct Answer**:
- Therefore, the correct answer is (a) 0.45.

### Final Answer:
The urban population of the world is approximately **0.45**.

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