You need to select a simple random sample of three from nine friends who will participate in a survey. Assume the friends are numbered 1, 2, 3, 4, 5, 6, 7, 8, and 9. Select three friends, using the first row of digits in the random number table. Read off each digit, skipping any digit not assigned to one of the friends. The sampling is without replacement, meaning that you cannot select the same person twice. Write down the numbers chosen.
\begin{tabular}{ccccc}
& $(1)$ & $(\mathbf{2})$ & $(3)$ & $(4)$ \\
1 & 54105 & 03042 & 58811 & 41590 \\
2 & 06053 & 27367 & 11152 & 46533 \\
3 & 74943 & 78866 & 62684 & 23574
\end{tabular}
What are the numbers of the three subjects selected?
\[
\square, \square, \square
\]
Answer
So, the numbers of the three friends selected are \(\boxed{5}\), \(\boxed{4}\), and \(\boxed{1}\).
Step 1 ：The first row of digits is: \(54105 03042 58811 41590\)
Step 2 ：Reading off each digit, we get:
Step 3 ：5 - This is a valid number, so we select friend number 5.
Step 4 ：4 - This is a valid number, so we select friend number 4.
Step 5 ：1 - This is a valid number, so we select friend number 1.
Step 6 ：0 - This is not a valid number, so we skip it.
Step 7 ：5 - This number has already been selected, so we skip it.
Step 8 ：0 - This is not a valid number, so we skip it.
Step 9 ：3 - This is a valid number, but we have already selected three friends, so we stop here.
Step 10 ：So, the numbers of the three friends selected are \(\boxed{5}\), \(\boxed{4}\), and \(\boxed{1}\).
