Reading tables on ACT Science: orienting to the rows, columns, and units, locating a value at an intersection, and tracking how one variable changes while another is held fixed.

What this topic is asking

After line graphs, the most common Interpretation of Data task is reading a table. ACT tables are often dense, with several variables across many rows and columns, and the test is whether you can navigate to the value the question wants and track a trend without getting lost. The skill is orientation and discipline, not arithmetic.

Orient to the table first

Just as with a graph, the first move is orientation. Spend two seconds learning the table's structure before hunting for a number:

• Title or caption: what the table is about, and which experiment or study it belongs to.
• Column headers: what each column measures, and in what units (grams, seconds, degrees Celsius, percent).
• Row labels: what distinguishes the rows (often the values of an independent variable, or the trial number).

Finding a value at an intersection

Reading a single value is a row-and-column lookup:

1. Identify the row that matches the condition the question states (for example, 40 degrees Celsius, or Trial 3).
2. Identify the column that holds the quantity asked for (for example, solubility).
3. Read the number at their intersection.

When a table is split into blocks (one block per solution, per material, or per experiment), first find the right block, then do the row-and-column lookup inside it. Reading the right row in the wrong block is a frequent slip.

Tracking a trend across rows

To find how one variable affects another, read down a single column while the row variable changes, keeping any other variables fixed:

• If the column values rise as the row variable rises, the relationship is direct.
• If they fall, the relationship is inverse.
• If they stay roughly constant, there is no relationship.

This is the table version of naming a trend on a graph, and it is the same logic developed in reading line graphs and trends.

Isolating one variable among several

ACT tables often vary two or more independent variables at once. To study the effect of just one, find two rows that differ only in that variable and compare their results. Holding the others constant is exactly the controlled-comparison logic used in experiments, covered in variables, controls, and experimental design.

When the answer needs two reads

Some questions combine a lookup with a calculation, for example "by how much did solubility increase between 20 and 60 degrees?" Read both intersections, then subtract: if solubility is 32 g at 20 degrees and 110 g at 60 degrees, the increase is $110 - 32 = 78$ g. The arithmetic is light; the care is in pulling the two correct values first.

Try this

Q1. Describe the three-step lookup for finding a single value in a data table. [2 points]

• Cue. Find the row matching the condition, find the column holding the asked quantity, and read the number at their intersection (first finding the correct block if the table is blocked).

Q2. A table varies both light intensity and temperature. To test the effect of light intensity alone, which rows should you compare? [2 points]

• Cue. Rows that differ only in light intensity, with temperature (and any other variable) held constant.