Chapter 19: Graphs 269How to Read It
When you begin to read a circle graph, the first thing you want to know is what the graph
is talking about. Look for a title to tell you the general topic. This graph shows how the list
of students who made the honor roll breaks down by class. Sometimes the graph will have a
caption to explain more clearly what it’s talking about. Next, look to the labels on the circle
wedges. They should tell you what each of the wedges represents, and they may have values or
percentages to tell you what part of the whole that wedge is. The graph below has four wedges,
each labeled with the name of a class, and each has a percent that tells you what part of the honor
roll comes from that class.
Sometimes your wedges are too small for
labels or your labels are too long to fit
neatly. Placing the label outside the circle
near the wedge is the next best option,
but if there are many small wedges, even
that may be hard to do. In that case, the
graph should have a legend. A legend is a
small box near the graph that explains the
code that you need to make sense of the
graph. It should tell you what each color or
pattern represents and probably include the
percentages or values as well.Honor Roll Membership
Freshman
26%Juniors
23%Seniors
33%Sophomores
18%CHECK POINT- Draw a circle graph to represent the data below.
Land Area of NYC by Borough
Borough Manhattan The Bronx Brooklyn Queens Staten Island
Land area
(square m iles)23 42 71 109 58- The largest borough (by land area) is approximately how many times larger than
the smallest?