Vital index of population is

Options

A. `(B//D)xx100`
B. `B-D`
C. (D//B)xx100`
D. `B+D`

Answer

To solve the question regarding the vital index of a population, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Concept**: The vital index of a population is a measure that compares the birth rate to the death rate. It helps in understanding the growth dynamics of a population.

2. **Defining Birth and Death Rates**:
- **Birth Rate (Natality)**: This is the number of births per thousand individuals in a population.
- **Death Rate (Mortality)**: This is the number of deaths per thousand individuals in a population.

3. **Formula for Vital Index**: The vital index can be mathematically expressed as:
\[ \text{Vital Index} = \left(\frac{\text{Birth Rate (b)}}{\text{Death Rate (d)}}\right) \times 100 \]
This formula indicates that the vital index is the ratio of the birth rate to the death rate, multiplied by 100.

4. **Identifying the Correct Option**: From the options provided in the question:
- Option 1: \( \frac{b}{d} \times 100 \) (This is the correct formula for the vital index)
- Option 2: \( b - d \times 100 \)
- Option 3: \( \frac{d}{b} \times 100 \)
- Option 4: \( b + d \)

The correct answer is the first option: \( \frac{b}{d} \times 100 \).

### Final Answer:
The vital index of a population is given by the formula \( \frac{b}{d} \times 100 \).

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