Worked example 2 Represent the following data on a pie chart.
Favourite sport No. of students
Solution Soccer 72°
Soccer 4
Hurling Basketball Rugby Football 5
6 1 4
Favourite sports Football
● Rugby ● 18° ● Basketball Hurling 72° 108°
72° 90°
Soccer
Stem and leaf plots
A stem and leaf plot is a special table where each data value is split into a ‘stem’ (the fi rst digit or digits) and a ‘leaf’ (usually the last digit).
Stem and leaf plots are used to display numerical data. In a stem and leaf plot the data is spread evenly along a branch in numerical order. Each data value is split into a stem and a leaf. ●
The digit(s) with the largest place value is referred to as the stem. ●
The digit with the smallest place value is referred to as the leaf (leaves).
For example, in the number 32, 3 is the stem and 2 is the leaf and in the number 11 · 5, 11 is the stem and 5 is the leaf.
The stem is placed in a column and the leaves are placed in rows to the right (or left) of the column, corresponding to their stems. Each value is seen, and data is sorted in ascending numerical order, from smallest to biggest.
Each stem and leaf plot must include a key to explain how to read the plot, and you must include appropriate units on the key, if there are any.