To solve the problem \(2.13 + 1\) and express the answer to the correct number of significant figures, we follow these steps:
1. Identify the given numbers and their significant figures:
- The number \(2.13\) has 3 significant figures.
- The number \(1\) has 1 significant figure.
2. Add the given numbers:
[tex]\[
2.13 + 1 = 3.13
\][/tex]
3. Determine the correct number of significant figures for the result:
When adding or subtracting numbers, the result should be rounded to the least number of decimal places present in any of the original numbers. Here:
- \(2.13\) has 2 decimal places.
- \(1\) has 0 decimal places.
Since 1 has the least number of decimal places (0 decimal places), the result should be rounded to the nearest whole number.
4. Round the result to the nearest whole number:
[tex]\[
3.13 \approx 3.1
\][/tex]
The correct answer to the problem \(2.13 + 1\) expressed to the correct number of significant figures is:
[tex]\[
\boxed{3.1}
\][/tex]
So, the correct option is C. 3.1
