Why Do We Use Graphs?
Imagine you have a giant spreadsheet with hundreds of numbers. It would take a long time to figure out what's going on! A graph (a picture that shows data using lines, bars, or points) turns those numbers into something you can see at a glance. People have been drawing graphs for centuries to make sense of information.
On the SSAT, you will look at a graph and choose the statement that correctly describes what the data shows. The big question is: How do you read a graph carefully enough to tell the true statements from the false ones?
Core Principles of Reading Graphs
Before you can pick the right answer, you need to understand a few building blocks. Every graph has parts that work together to tell a story.
Axes & Labels
Scale & Units
Trend (Direction)
Specific Values
Comparing Sections
Reading a Line Graph — Visual Explanation
Below is a line graph showing how many books a student named Mia read each month from January through June. Study the diagram, then read the explanation underneath.
Notice a few things. First, the overall trend is increasing — the line goes up as you move to the right. Second, the biggest single jump is from April (6 books) to May (8 books), a gain of 2 books. Third, every month Mia read more than the month before, so there is no decrease anywhere in this graph.
If a test question asked, "Which statement about the graph is true?" you would check each answer choice against these observations. A wrong choice might say "Mia read the most books in April" — but the graph clearly shows June is the highest point.
Using Numbers to Confirm Trends
Sometimes "eyeballing" a graph isn't enough. You can use simple math to check whether a statement is true. Here are the two main tools you'll need.
For Mia's graph, the change from January to June is 9 − 3 = 6 books. If an answer choice said "Mia read 5 more books in June than in January," you would know that is false because the actual difference is 6, not 5.
Bar Graphs, Line Graphs & More
The SSAT can show you different kinds of graphs. Each type tells the story in a slightly different way. Let's look at a bar graph next so you can practice the same skills on a different format.
With a bar graph, you compare the heights (or lengths) of the bars. A taller bar means a larger value. To find a difference, subtract: Soccer − Basketball = 36 − 30 = 6 more students chose soccer.
| Graph Type | Best For | How to Spot a Trend |
|---|---|---|
| Line Graph | Showing change over time | See if the line goes up, down, or stays flat |
| Bar Graph | Comparing categories | Compare bar heights side by side |
| Pie Chart | Showing parts of a whole | Larger slices represent larger portions |
Worked Example — Picking the True Statement
Let's walk through a problem step by step using the Favorite Sport bar graph from Section 5. Suppose the question says:
Common Mistakes & How to Avoid Them
| Mistake | Why It Happens | How to Fix It |
|---|---|---|
| Misreading the scale | You assume each gridline is 1 when it is really 5 or 10. | Read the numbers printed on the y-axis before doing any math. |
| Confusing "increase" with "highest" | A statement says the biggest increase happens in a certain month, but you pick the month with the highest total instead. | "Increase" means the change between two points, not the point itself. Subtract to find the change. |
| Ignoring one answer choice | You stop testing after finding one choice that seems right. | Always test all five choices to be sure. Two may look close. |
| Reading the wrong bar or point | Bars or points are close together, and you read the neighboring one. | Trace a finger (or pencil) straight up from the label to the bar top, then across to the y-axis. |
Connecting to Harder Graph Skills
Once you master reading single graphs, you'll encounter questions that ask you to do more. Here's how today's skill connects to topics you'll see later.
| Today's Skill | Advanced Version |
|---|---|
| Read one data point | Interpolate (estimate a value between two points) |
| Identify an overall trend (up or down) | Calculate rate of change (slope) between two points |
| Compare two bars | Compare data from two different graphs at once (double bar or double line) |
| Pick a true statement | Predict future values by extending a trend |
You don't need these advanced skills for the SSAT Middle Level, but knowing they exist can make you feel confident. The reading, subtracting, and comparing you're learning now is the foundation for all of them.
Practice Problems
Use the data described in each problem. For problems 1–3, refer to this data set for a line graph showing daily high temperatures for a school week: Monday 58°F, Tuesday 62°F, Wednesday 60°F, Thursday 65°F, Friday 70°F.
Lesson Summary
To interpret trends in a graph, start by reading the title, axis labels, and scale so you know what the graph is measuring. Next, identify the overall trend — is the data going up, going down, or staying flat? Then use subtraction to find exact differences between values when a question asks "how much more" or "how much less."
When you face a multiple-choice question, test every answer choice against the data in the graph. Eliminate choices that don't match the numbers or the trend, and you'll find the one true statement. Watch out for tricky wording like "greatest increase" versus "greatest value" — they mean different things. With practice, you'll read graphs quickly and confidently on test day.