How many significant figures are there in the value `250xx10^10` m?

Answer

To determine the number of significant figures in the value \( 250 \times 10^{10} \) m, we can follow these steps:

### Step 1: Identify the digits in the number
The number given is \( 250 \). We need to look at each digit in this number to determine how many are significant.

### Step 2: Apply the rules of significant figures
1. **Rule 1**: The power of 10 does not count as a significant figure. Therefore, we can ignore \( 10^{10} \) for our count.
2. **Rule 2**: All non-zero digits are counted as significant figures. In \( 250 \), the digits '2' and '5' are non-zero, so they are both significant.
3. **Rule 3**: Any zeros that are between non-zero digits or at the end of a number with a decimal point are significant. In this case, the zero in \( 250 \) is at the end of the number and follows non-zero digits, which means it is also counted as significant.

### Step 3: Count the significant figures
Now, we can count the significant figures:
- The digit '2' is significant.
- The digit '5' is significant.
- The digit '0' is also significant (because it is at the end of the number).

Thus, the total number of significant figures in \( 250 \) is 3.

### Conclusion
The number \( 250 \times 10^{10} \) m has **3 significant figures**.

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