The population of a country is 3 .2 `xx 10^6` . If there are `8 xx 10^5` children, then find the number of adults.

Options

A. `3 xx 10^3`
B. `8 xx 10^3`
C. `2.4 xx 10^6`
D. `2.4 xx 10^5`

Answer

To solve the problem step by step, we need to find the number of adults in a country given the total population and the number of children.

### Step-by-Step Solution:

1. **Identify the total population and the number of children:**
- The total population of the country is given as \( 3.2 \times 10^6 \).
- The number of children is given as \( 8 \times 10^5 \).

2. **Convert the scientific notation to standard form:**
- \( 3.2 \times 10^6 = 3,200,000 \) (This is the total population).
- \( 8 \times 10^5 = 800,000 \) (This is the number of children).

3. **Set up the equation to find the number of adults:**
- The number of adults can be calculated by subtracting the number of children from the total population:
\[ \text{Number of adults} = \text{Total population} - \text{Number of children} \]

4. **Substitute the values into the equation:**
\[ \text{Number of adults} = 3,200,000 - 800,000 \]

5. **Perform the subtraction:**
\[ 3,200,000 - 800,000 = 2,400,000 \]

6. **Convert the result back to scientific notation:**
- \( 2,400,000 = 2.4 \times 10^6 \).

7. **Final answer:**
- The number of adults in the country is \( 2.4 \times 10^6 \).