If 40 is `0.05%` of x, then what is the value of x ?

Options

A. `80000`
B. `8000`
C. `800`
D. `80`

Answer

To solve the problem "If 40 is 0.05% of x, then what is the value of x?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the percentage relationship**: We know that 0.05% of x is equal to 40. We can express this mathematically as:
\[ 0.05\% \times x = 40 \]

2. **Convert percentage to decimal**: To work with percentages, we convert 0.05% to a decimal.
\[ 0.05\% = \frac{0.05}{100} = 0.0005 \]

3. **Set up the equation**: Now we can rewrite the equation using the decimal:
\[ 0.0005 \times x = 40 \]

4. **Isolate x**: To find x, we need to divide both sides of the equation by 0.0005:
\[ x = \frac{40}{0.0005} \]

5. **Perform the division**: Now, calculate the value of x:
\[ x = 40 \div 0.0005 = 40 \times 2000 = 80000 \]

6. **Final answer**: Therefore, the value of x is:
\[ x = 80000 \]

### Summary of the Solution:
The value of x is 80000.

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