4.5.1 Stem & Leaf diagrams

4.5.1 Stem Leaf diagrams

A stem-and-leaf diagram is a way of organizing and displaying numerical data.

• It is a simple and effective tool for summarizing large amounts of data and identifying patterns and outliers.
• In a stem-and-leaf diagram, each number is split into two parts: the stem and the leaf.
• To draw a stem-and-leaf diagram
  • Identify the stems and leaves for each number in your data set.
  • The stem is the leftmost digit or digits, and the leaf is the rightmost digit.
  • Write the stems in a vertical column on the left side of your page.
    • Be sure to leave enough space to write the leaves for each stem.
  • Write the leaves for each stem in a row to the right of the stem.
    • The leaves should be written in ascending order.
    • If there are multiple leaves for a stem, separate them with a space or a comma.
  • Label your diagram with a title that describes the data set and any other important information, such as the units of measurement.

Worked example:

Here are the ages, in years, of \( 15 \) students.

Show this information in an ordered stem and leaf diagram.

You must write down all stages in your working.

Identify the stems and leaves for each number in your data set

The stem is the leftmost digit or digits, and the leaf is the rightmost digit

E.g., \( 19 \) will have a stem of \( 1 \) and a leaf of \( 9 \).

Stems are already in order, so we need to put leaves in order too

Don’t forget to add a key with your final answer

Key: \( 3 \)| \( 9 \) means \( 39 \) years