Stem and leaf plots review

A stem and leaf plot displays numerical data by splitting each data point into a "leaf" (usually the last digit) and a "stem" (the leading digit or digits).

For example, the buyer for a chain of department stores counted the number of pairs of boots at each of the stores and made a stem and leaf plot for the data. Here is the dataset and the stem and leaf plot:

Dataset: $17$17, $18$18, $20$20, $25$25, $28$28, $34$34, $34$34, $37$37, $38$38, $50$50

Stem and leaf plot:

$\begin{aligned} &1~~|~~7~~8\\ &2~~|~~0~~5~~8\\ &3~~|~~4~~4~~7~~8\\ &4~~|\\ &5~~|~~0\\ \end{aligned}$
Key: $1~|~8$1, space, vertical bar, space, 8 represents a store that had $18$18 pairs of boots.

Here's how to make a stem and leaf plot step by step. We'll use the same dataset as before. Here it is again:

$17$17, $18$18, $20$20, $25$25, $28$28, $34$34, $34$34, $37$37, $38$38, $50$50

Step 1: Split each data point into a stem and a leaf. The stem is everything before the final digit, and the leaf is the final digit. Write the stems in a vertical column and don't skip stems just because they don't have any data.

$\blueD1|7$start color #11accd, 1, end color #11accd, vertical bar, 7, $\blueD1|8$start color #11accd, 1, end color #11accd, vertical bar, 8, $\blueD2|0$start color #11accd, 2, end color #11accd, vertical bar, 0, $\blueD2|5$start color #11accd, 2, end color #11accd, vertical bar, 5, $\blueD2|8$start color #11accd, 2, end color #11accd, vertical bar, 8, $\blueD3|4$start color #11accd, 3, end color #11accd, vertical bar, 4, $\blueD3|4$start color #11accd, 3, end color #11accd, vertical bar, 4, $\blueD3|7$start color #11accd, 3, end color #11accd, vertical bar, 7, $\blueD3|8$start color #11accd, 3, end color #11accd, vertical bar, 8, $\blueD5|0$start color #11accd, 5, end color #11accd, vertical bar, 0

Our $\blueD{\text{stems}}$start color #11accd, start text, s, t, e, m, s, end text, end color #11accd are the tens digits:

$\begin{aligned} &1~~|\\ &2~~|\\ &3~~|\\ &4~~|\\ &5~~|\\ \end{aligned}$
Step 2: Write each leaf next to its corresponding stem. The $\greenD{\text{leaves}}$start color #1fab54, start text, l, e, a, v, e, s, end text, end color #1fab54 should go from smallest to largest. Our leaves are the ones digits.

$1|\greenD7$1, vertical bar, start color #1fab54, 7, end color #1fab54, $1|\greenD8$1, vertical bar, start color #1fab54, 8, end color #1fab54, $2|\greenD0$2, vertical bar, start color #1fab54, 0, end color #1fab54, $2|\greenD5$2, vertical bar, start color #1fab54, 5, end color #1fab54, $2|\greenD8$2, vertical bar, start color #1fab54, 8, end color #1fab54, $3|\greenD4$3, vertical bar, start color #1fab54, 4, end color #1fab54, $3|\greenD4$3, vertical bar, start color #1fab54, 4, end color #1fab54, $3|\greenD7$3, vertical bar, start color #1fab54, 7, end color #1fab54, $3|\greenD8$3, vertical bar, start color #1fab54, 8, end color #1fab54, $5|\greenD0$5, vertical bar, start color #1fab54, 0, end color #1fab54

$\begin{aligned} &1~~|~~7~~8\\ &2~~|~~0~~5~~8\\ &3~~|~~4~~4~~7~~8\\ &4~~|\\ &5~~|~~0\\ \end{aligned}$
Step 3: Give a key that explains what a stem and leaf represent.

$\begin{aligned} &1~~|~~7~~8\\ &2~~|~~0~~5~~8\\ &3~~|~~4~~4~~7~~8\\ &4~~|\\ &5~~|~~0\\ \end{aligned}$
Key: $1~|~8$1, space, vertical bar, space, 8 represents a store that had $18$18 pairs of boots.

A zookeeper published the following stem-and-leaf plot showing the number of bears at each major zoo in the country:

$\begin{aligned} &0~~|\\ &1~~|~~8~~8\\ &2~~|~~1~~3~~6~~6~~7~~7~~9\\ &3~~|~~1~~7\\ &4~~|~~1~~4~~5~~7\\ &5~~|~~0~~3\\ \end{aligned}$
Key: $1~|~8$1, space, vertical bar, space, 8 represents a zoo that has $18$18 bears.