Questions: 110 adults with gum disease were asked the number of times per week they used to floss before their diagnoses. The (incomplete) results are shown below:
# of times floss per week Frequency Relative Frequency Cumulative Frequency
------------
0 13 0.1182 13
1 16 0.1455 29
2 18 0.1636 47
3 12 0.1091 59
4 15 74
5 13 0.1182
6 0.1091 99
7 11 0.1 110
a. Complete the table (Use 4 decimal places when applicable)
b. What is the cumulative relative frequency for flossing 4 times per week? %
Transcript text: 110 adults with gum disease were asked the number of times per week they used to floss before their diagnoses. The (incomplete) results are shown below:
\begin{tabular}{|c|c|c|c|}
\hline \begin{tabular}{c}
\# of times \\
floss per \\
week
\end{tabular} & Frequency & \begin{tabular}{c}
Relative \\
Frequency
\end{tabular} & \begin{tabular}{c}
Cumulative \\
Frequency
\end{tabular} \\
\hline 0 & 13 & 0.1182 & 13 \\
\hline 1 & 16 & 0.1455 & 29 \\
\hline 2 & 18 & 0.1636 & 47 \\
\hline 3 & 12 & 0.1091 & 59 \\
\hline 4 & 15 & & 74 \\
\hline 5 & 13 & 0.1182 & \\
\hline 6 & & 0.1091 & 99 \\
\hline 7 & 11 & 0.1 & 110 \\
\hline
\end{tabular}
a. Complete the table (Use 4 decimal places when applicable)
b. What is the cumulative relative frequency for flossing 4 times per week? $\square$ \%
Solution
Solution Steps
Step 1: Complete the Relative Frequency for Flossing 4 Times per Week
The relative frequency is calculated as:
\[
\text{Relative Frequency} = \frac{\text{Frequency}}{\text{Total Number of Adults}}
\]
For flossing 4 times per week:
\[
\text{Relative Frequency} = \frac{15}{110} = 0.1364
\]
Step 2: Complete the Cumulative Frequency for Flossing 5 Times per Week
The cumulative frequency is the sum of all frequencies up to and including the current row. For flossing 5 times per week:
\[
\text{Cumulative Frequency} = 74 + 13 = 87
\]
Step 3: Complete the Frequency for Flossing 6 Times per Week
The frequency can be calculated using the relative frequency:
\[
\text{Frequency} = \text{Relative Frequency} \times \text{Total Number of Adults}
\]
For flossing 6 times per week:
\[
\text{Frequency} = 0.1091 \times 110 = 12
\]
Step 4: Calculate the Cumulative Relative Frequency for Flossing 4 Times per Week
The cumulative relative frequency is the sum of all relative frequencies up to and including the current row. For flossing 4 times per week:
\[
\text{Cumulative Relative Frequency} = 0.1182 + 0.1455 + 0.1636 + 0.1091 + 0.1364 = 0.6728
\]
Convert this to a percentage:
\[
\text{Cumulative Relative Frequency} = 0.6728 \times 100 = 67.28\%
\]