\begin{tabular}{l|llllllll}
1 & 7 & & & & & & \\
4 & 1 & 1 & 2 & 9 & & & \\
5 & 3 & 3 & 3 & 3 & 3 & & \\
6 & 1 & 3 & 4 & 6 & 7 & 8 & 9 \\
7 & 1 & 3 & 5 & 5 & 7 & & \\
8 & 2 & 2 & 3 & 4 & & \\
8
\end{tabular}

a. How many students were polled? [tex]$\square$[/tex]

b. Find the mean to the nearest cent. [tex]$\square$[/tex]



Answer :

Let's break down the steps to solve the given questions step by step.

a. How many students were polled?

1. Look at the given table and list out all the numbers, excluding any empty or missing entries:
[tex]\[ 1, 7, 4, 1, 1, 2, 9, 5, 3, 3, 3, 3, 3, 6, 1, 3, 4, 6, 7, 8, 9, 7, 1, 3, 5, 5, 7, 8, 2, 2, 3, 4, 8 \][/tex]

2. Count the numbers in the list:
[tex]\[ \text{Total number of students polled} = 33 \][/tex]

So, the number of students polled is:
[tex]\[ \boxed{33} \][/tex]

b. Find the mean to the nearest cent.

1. Add up all the numbers in the list:
[tex]\[ 1 + 7 + 4 + 1 + 1 + 2 + 9 + 5 + 3 + 3 + 3 + 3 + 3 + 6 + 1 + 3 + 4 + 6 + 7 + 8 + 9 + 7 + 1 + 3 + 5 + 5 + 7 + 8 + 2 + 2 + 3 + 4 + 8 = 144.0 \][/tex]

2. Divide the sum by the total number of students to find the mean:
[tex]\[ \text{Mean} = \frac{144.0}{33} \approx 4.36 \][/tex]

So, the mean to the nearest cent is:
[tex]\[ \boxed{4.36} \][/tex]

答案完成了:
\begin{enumerate}
\item The number of students polled is \( \boxed{33} \).
\item The mean to the nearest cent is [tex]\( \boxed{4.36} \)[/tex].