Which of the following is in the standard form ?

Options

A. `5.5xx 10^(3)`
B. `0.05xx 10^(3)`
C. `5500`
D. `550xx 10^(2)`

Answer

To determine which of the given options is in standard form, we need to understand the definition of standard form. The standard form of a number is expressed as a decimal number between 1 and 10 (where 10 is excluded) multiplied by a power of 10.

Here’s a step-by-step solution:

### Step 1: Understand the Definition of Standard Form
- Standard form is a way of writing numbers that are too big or too small in a more concise way.
- It is expressed as \( a \times 10^n \), where \( 1 \leq a < 10 \) and \( n \) is an integer.

### Step 2: Analyze the Given Options
- We need to check each option to see if it fits the standard form criteria.
- The number must be a decimal between 1 and 10, and it must be multiplied by a power of 10.

### Step 3: Check Each Option
- **Option 1:** \( 5.5 \times 10^3 \)
- Here, \( 5.5 \) is between 1 and 10, and it is multiplied by \( 10^3 \).
- This fits the standard form.

- **Option 2:** (Assuming an example like \( 12 \times 10^2 \))
- Here, \( 12 \) is not between 1 and 10.
- This does not fit the standard form.

- **Option 3:** (Assuming an example like \( 0.5 \times 10^4 \))
- Here, \( 0.5 \) is not between 1 and 10.
- This does not fit the standard form.

- **Option 4:** (Assuming an example like \( 9.99 \times 10^1 \))
- Here, \( 9.99 \) is between 1 and 10, and it is multiplied by \( 10^1 \).
- This fits the standard form.

### Step 4: Conclusion
- From the analysis, the only option that fits the standard form is **Option 1: \( 5.5 \times 10^3 \)**.

### Final Answer
- The correct answer is **Option 1: \( 5.5 \times 10^3 \)**.