Express the following number in standard form:
`39087.8`

Answer

To express the number `39087.8` in standard form, we follow these steps:

### Step 1: Identify the first non-zero digit
The first non-zero digit in `39087.8` is `3`.

### Step 2: Write the number in decimal form
We need to express the number in the form of `a × 10^n`, where `a` is a number between `1` and `10`. To do this, we write `39087.8` as `3.90878`.

### Step 3: Determine the power of 10
Next, we need to determine how many places we moved the decimal point to get from `39087.8` to `3.90878`.

- The original number is `39087.8`, and we moved the decimal point 4 places to the left to get to `3.90878`.

### Step 4: Write the final expression
Now we can express the number in standard form:
\[ 39087.8 = 3.90878 \times 10^4 \]

### Final Answer
Thus, the number `39087.8` in standard form is:
\[ 3.90878 \times 10^4 \]

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