Resources for Dot Plots, Stem and Leaf Plots
-
Questions
7
With Worked SolutionClick Here -
Video Tutorials
1
Click Here
Dot Plots, Stem and Leaf Plots Theory
![\begin{multicols}{2} \textbf{Example 1}\\ Use the stem and leaf plot to answer the following questions. \begin{center} \begin{tabular}{c|l} \hline \multicolumn{2}{c}{ Statistics Test Scores } \\ \hline \multicolumn{1}{l}{ Stem } & Leaf \\ \hline 5 & 1\;\;4\;\;7 \\ \hline 6 & 3\;\;3\;\;5\;\;6 \\ \hline 7 & 7\;\;8\;\;8\;\;8\;\;9\;\;9 \\ \hline 8 & 5\;\;6\;\;6\;\;8 \\ \hline 9 & 1\;\;2\;\;2 \\ \hline \end{tabular} \end{center} For the given stem and leaf plot, find:\\ \textbf{i)} The range\\ \textbf{ii)} The mode\\ \textbf{iii)} The median\\ \textbf{iv)} The mean.\\ \textbf{Example 1 solution}\\ \textbf{i)} \(\begin{aligned}[t] \text { Range } & =\text { highest score }- \text { lowest score } \\ & =92-51 \\ & =41 \end{aligned}\)\\ \textbf{ii)} \(\begin{aligned}[t] \text { Mode } & =\text { score with the highest frequency } \\ & =78 \end{aligned}\)\\ \textbf{iii)} Median \(=\) average of the two middle scores since there is an even number of scores.\\ The 10th score \(=78\), the 11th score \(=78\)\\[3pt] \(\begin{aligned} \text { Median }&=\frac{78+78}{2} \\ =78 \end{aligned}\)\\ \textbf{iv)} \(\begin{aligned}[t] \text { Mean } & =\frac{\text { sum of all the scores }}{\text { number of scores }} \\ & =\frac{51+54+\cdots+92}{20} \\ & =\frac{1508}{20} \\ & =75.4 \end{aligned}\) \columnbreak \textbf{Example 2}\\ Twenty students were given a statistics test that was marked out of 10. The following dot plot shows the results. \begin{center} \begin{tikzpicture}[scale=0.7] \draw[line width=1pt] (-1,0)--(11,0); \foreach \a in {1} \draw[fill=black] (3,\a) circle (0.1); \foreach \b in {1,2} \draw[fill=black] (4,\b) circle (0.1); \foreach \c in {1,2,3} \draw[fill=black] (5,\c) circle (0.1); \foreach \d in {1,2,3,4} \draw[fill=black] (6,\d) circle (0.1); \foreach \g in {1,2,3,4,5} \draw[fill=black] (7,\g) circle (0.1); \foreach \h in {1,2,3} \draw[fill=black] (8,\h) circle (0.1); \foreach \k in {1} \draw[fill=black] (9,\k) circle (0.1); \foreach \l in {1} \draw[fill=black] (10,\l) circle (0.1); \foreach \x in {0,1,...,10} \draw[thin] (\x,3pt )--(\x, -3pt ) node[anchor=north]{\Large\(\x\)}; \end{tikzpicture} \end{center} From the dot plot determine\\ \textbf{i)} The range\\ \textbf{ii)} The mode\\ \textbf{iii)} The median\\ \textbf{iv)} The mean\\ \textbf{Example 2 solution}\\ \textbf{i)} \(\begin{aligned}[t] \text { Range } & =10-3 \\ & =7 \end{aligned}\)\\ \textbf{ii)} Mode \(=7 \quad\) (frequency \(=5\) )\\[3pt] \textbf{iii)} \(\begin{aligned}[t] \text { Median } & =\frac{6+7}{2} \\ & =6.5 \end{aligned}\)\\[3pt] \textbf{iv)} \(\begin{aligned}[t] \text { Mean } & =\frac{3+4+4+\cdots+9+10}{20} \\ & =\frac{128}{20} \\ & =6.4 \end{aligned}\) \end{multicols}](/media/3hbfhdew/9225.png)