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Understanding Tables, Graphs, and Figures


This Magoosh ACT lesson is all about understanding and reading tables, graphs and figures on the ACT Science Test. Much of this will be a basic review for most of you but because how to read charts and graphs is a topic that many students have not explicitly studied in a really, really long time, if ever. It's worth taking a look at here, because it is the biggest part of achieving success on the ACT Science Test.

In other videos following this one, we're gonna go even deeper into this topic and look at how to identify trends and patterns on these tables, graphs, and figures. Or how to link different figures together. But here, let's start with some of the basics. On your screen, you see two examples of what the ACT is going to refer to as tables.

You might wanna call them charts, tomato, tomato, technically they're data tables. The first thing to notice about tables or graphs on the ACT is how important the labels are. You should get used to matching the key words and phrases that you see in the questions with the labels on the tables or the graphs that you may see. In fact, most of the key terms are going to be in these labels so, look at the top, the bottom, the left, and the right side of the graphs and diagrams as well as with in the graphs and figures themselves.

So in Table 2 here, for example. We should do a quick scan and note that the terms Voltage, Resistance, and Current appear across the top. And different trial numbers appear down the side. Now, I know this may seem pretty obvious, but it's something very specific that you can be directing your eyes to on the science test.

When you're looking at a test page that is just absolutely covered and overwhelmed with information. So practice first going straight to the labels. And data tables, as opposed to graphs, make it really easy to see all the exact numbers in the data. So you don't have to figure out what the number is by tracking a line in a line graph, to the vertical or the horizontal axis, for example.

But for the purpose of the ACT, you don't need to worry about why the ACT is choosing to present information in a certain way. You only need to know what to focus your eye, eyes on. So again, I know it makes an obvious, but for the purposes of finding information quickly under a time limit, you always want to be thinking about tables in terms of what information is linked together in rows and columns.

What are the trends that occur vertically in a column, and what are the relationships that are constructed horizontally. So for example, in Table 2, we can see that each column is tracking the percentage of patients on each particular drug combination who were free, I'm sorry, on Table 1, we see that each column is tracking the number of patients that were free of a parasite on each day of the trials.

So if we wanna focus specifically on, let's say, what's happening with Drug Combination C, we just wanna focus on these two columns, Drug Combination C. And you can see that in both cases, the patients are increasingly free of the parasite. But, let's say we're researchers who wanna know, what's happening on day 14 of the trial across all of the drug combinations.

Then we wanna hone in on that row. So day 14 and we wanna be highlighting either on the page or in our heads, day 14. What's going on there? So we can see that, in general, the drug combination is doing pretty good job keeping people parasite free, with the exception of Drug Combination D, not doing so hot.

So, we're gonna talk more about finding trends like this on tables in our next videos on finding trends pattens and links on the ACT. But for now, let's just say that for the purposes for this test, generally when you see a question asking you about the key term Drug combination D, for example. You want to focus in on the column or the row of data pertaining to that term, and I suggest you mark it directly on your task whenever possible.

So, if a question is asking me about Drug Combination D, I'm gonna circle these two columns so I can be focusing my eyes on what's important. Okay, let's talk about graphs now. The most common type of graphs you will see on the ACT are line graphs and bar graphs, and most often line graphs. There's a few things worth noting about graphs like these on the ACT.

Typically, you will see the independent variable tracked along the horizontal axis, and the dependent variable tracked along the vertical axis. So basically what this means in layman's terms is that what is changing in the experiment is tracked along the bottom. And the resulting effect is tracked along the vertical axis. So for example, in Figure 2, we have a chart taking a look at the correlation between the length of a biopsy and a positive test for lymphoma.

The independent variable, what the researchers are manipulating is the length of the biopsy. And what's dependent on that is the percentage testing positive which is marked along the vertical axis. I also wanna point out, because it has plagued students again and again, that the black and white formatting of ACT does make it really easy for students to get confused.

A dotted line on a line graph can look really similar to a dashed line, so you wanna be super careful that you are checking the right bit of data in the right place. Often, there's going to be more than one graph or table with similar or identical labels as well, so trained test-takers know, usually because they've already made this mistake on practice tests, to double check that they are looking at the right table or figure.

So for instance, if you come across a couple line graphs, like you see in Figure 1 here. You'll notice that both set of axes are the same and both graphs cover Drug Combination A and Drug Combination B. The difference is these unfamiliar terms. Plasmodium falciparum and Plasmodium vivax.

I can't tell you how many quite, students get a question wrong like this because they look at the wrong graph. Because you can bet that the data from that other graph is going to appear as incorrect answer choice. Something else to notice on charts and graphs are the points where something interesting is happening in the data.

So, for example. Where does the data spike or dip? Where does it level off? Where does it change in some way? The ACT is often will going to target these points in the questions. So, for example, if we had a graph like this one, looking at Sample X, this is a notable point, this is where it spiked and then for some reason, it started to drop again.

Or for Sample Y, something happened here. It stopped increasing, it leveled off. You can bet that in some way, even though it may not be incredibly obvious, the ACT is probably going to ask you about these points. You're gonna see a lot of other types of figures and charts in the ACT and you can't lump them all in one category, but I just want to make a quick note here about the explanatory charts and diagrams you might see on the test and the passages.

Such as the examples you see on your screen. Pay attention to these. Now, the ACT is not going to test you on all the information in the passage. But, if you see an explanatory chart or diagram in the passage, meaning one that is there to help you understand the scientific sit, situation, pay particular attention to it.

It usually means that the ACT thought something was sufficiently complex, that it would be better presented in a visual format rather than text. And often, going to this extra work means that you'll be using it in some capacity. So it's far better time spending a little more time focusing on these explanatory figures of DNA replication models or pollutant standards, than any of the text in the passage.

Finally, just a forewarning that the ACT usually does like to throw some strange figures or illustrations at you. And this is not because you are expected to understand really complex scientific situations and figures. But to make sure that you understand the fundamentals of presenting scientific data and know how to apply these principles to lots of different figures and graphs.

So for example, let's look at this ACT figure from the preparing for the ACT guide, available for free on And, try not to be intimidated, okay? So let's focus on the labels. We have frequency over here. Intensity down here.

We know these lines up here are S something. Some type of percentage. And the dashed line means something's in air and a dotted line means something's in water. Now, we don't have to necessarily understand this to answer the questions. When you go to the questions, they're gonna ask you to find some of these key terms.

They're gonna say something about frequency, what's frequency or what's intensity at 120. And all you need to do is find where that point is on the line or the curve, or what's happening to a line or a curve between two points. If you do this, you're going to be just fine, even if you don't understand the overall picture.

In our next video, looking at finding patterns and trends in the ACT Science Test. We're gonna go in a little bit more detail about the slope of lines, and curves, and how to infer what's happening to the data simply by eyeballing the figures, and charts. So, make sure to check that out for part two of this discussion of tables, graphs, and figures.

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