To solve this problem, follow these steps:
1. Count the number of students with at least one, but no more than two, siblings:
- Students with 1 sibling: [tex]\(18\)[/tex]
- Students with 2 siblings: [tex]\(10\)[/tex]
Add these two numbers together to find the total number of students with at least one, but no more than two, siblings:
[tex]\[
18 + 10 = 28
\][/tex]
2. Calculate the total number of students surveyed:
Add the numbers of students in each category:
- Students with 0 siblings: [tex]\(4\)[/tex]
- Students with 1 sibling: [tex]\(18\)[/tex]
- Students with 2 siblings: [tex]\(10\)[/tex]
- Students with 3 siblings: [tex]\(8\)[/tex]
So, the total number of students is:
[tex]\[
4 + 18 + 10 + 8 = 40
\][/tex]
3. Determine the experimental probability:
The probability is the ratio of the number of students with at least one, but no more than two, siblings to the total number of students. Therefore, the probability is:
[tex]\[
\frac{28}{40}
\][/tex]
Convert this fraction to a percentage by multiplying by 100:
[tex]\[
\left(\frac{28}{40}\right) \times 100 = 70\%
\][/tex]
4. Round the result to the nearest whole percent:
The probability is already a whole number, so no further rounding is needed.
Therefore, the experimental probability that a 10th-grade student chosen at random has at least one, but no more than two, siblings is:
[tex]\[
\boxed{70\%}
\][/tex]
So, the correct answer is [tex]\(70\%\)[/tex].
