The table shows the results of a survey in which 10th-grade students were asked how many siblings (brothers and/or sisters) they have.

[tex]\[
\begin{tabular}{|c|c|}
\hline
\text{Number of Siblings} & \text{Number of Students} \\
\hline
0 & 4 \\
\hline
1 & 18 \\
\hline
2 & 10 \\
\hline
3 & 8 \\
\hline
\end{tabular}
\][/tex]

What is the experimental probability that a 10th-grade student chosen at random has at least one, but no more than two, siblings? Round to the nearest whole percent.

A. 65%
B. 70%
C. 75%
D. 80%



Answer :

To find the experimental probability that a 10th-grade student chosen at random has at least one, but no more than two, siblings, we need to perform the following steps:

1. Identify and Sum Up the Total Number of Students Surveyed:

The numbers of students with 0, 1, 2, and 3 siblings are given in the table:
- Students with 0 siblings: 4
- Students with 1 sibling: 18
- Students with 2 siblings: 10
- Students with 3 siblings: 8

Summing these values, we get the total number of students surveyed:
[tex]\[ 4 + 18 + 10 + 8 = 40 \][/tex]

2. Determine the Number of Students with 1 or 2 Siblings:

The numbers of students with 1 and 2 siblings are:
- Students with 1 sibling: 18
- Students with 2 siblings: 10

Summing these values, we get the number of students with 1 or 2 siblings:
[tex]\[ 18 + 10 = 28 \][/tex]

3. Calculate the Experimental Probability:

The experimental probability is the ratio of the number of students with 1 or 2 siblings to the total number of students, multiplied by 100 to get a percentage:
[tex]\[ \left( \frac{28}{40} \right) \times 100 = 70.0\% \][/tex]

4. Round to the Nearest Whole Percent:

We already have a calculation of 70.0%, and this rounded to the nearest whole percent remains 70%.

Therefore, the experimental probability that a 10th-grade student chosen at random has at least one but no more than two siblings, rounded to the nearest whole percent, is [tex]\(\boxed{70\%}\)[/tex].