Data Representation passages give you tables and graphs with a short introduction, and about five or six questions. Most of them are lookups: find the row, find the column, read the value.
These are the fastest points available anywhere on the ACT, and students lose them to carelessness rather than difficulty.
How to answer these
Read the axes before the prose. Name what is on each axis and in what units, before question one. Fifteen seconds here prevents the most common error on the section.
Track with your finger. Put your pencil on the row and slide across to the column. It looks slow and it is faster than getting it wrong.
Say the trend as a sentence. 'As temperature increases, solubility increases.' Then find the option that says that.
Bound, do not calculate. If a value sits between two rows, the answer must sit between their values. That kills two or three options with no arithmetic.
What the wrong answers look like
The adjacent row. You read the value one row above or below the one asked for. Six-row tables exist for this reason.
The other column. Two conditions tabulated side by side, and you took the wrong one.
Unit mismatch. The table is in minutes and the options are in seconds, or grams per 100 g against kilograms.
The trend that turns. A column that rises to a peak then falls is not 'increases only', and that option will be sitting right there.
Practice questions
Four real questions from the CruxStudy bank, with the keyed answer marked and the explanation behind a click so you can try them first.
Example 1Easier
A student measured the solubility of two salts, Salt X and Salt Y. For each trial, the student added salt in small amounts to 100 g of water held at a set temperature, stirring until no more salt would dissolve. The mass of salt that had dissolved at that point, in grams per 100 g of water, was recorded as the solubility of that salt at that temperature. Results are shown in Table 1.
Water temp (°C)
Salt X solubility (g/100 g water)
Salt Y solubility (g/100 g water)
10
22
74
20
31
68
30
42
62
40
48
57
50
70
53
60
88
49
According to Table 1, the solubility of Salt X at 30 °C is:
22 g per 100 g water
42 g per 100 g water correct
62 g per 100 g water
88 g per 100 g water
Show the explanation
In the 30 °C row of Table 1, the Salt X column reads 42 g per 100 g of water. The value 62 is Salt Y at that same temperature, 22 is Salt X at 10 °C, and 88 is Salt X at 60 °C.
Example 2Medium
A student measured the solubility of two salts, Salt X and Salt Y. For each trial, the student added salt in small amounts to 100 g of water held at a set temperature, stirring until no more salt would dissolve. The mass of salt that had dissolved at that point, in grams per 100 g of water, was recorded as the solubility of that salt at that temperature. Results are shown in Table 1 and Figure 1.
Water temp (°C)
Salt X solubility (g/100 g water)
Salt Y solubility (g/100 g water)
10
22
74
20
31
68
30
42
62
40
48
57
50
70
53
60
88
49
Based on Table 1 and Figure 1, the solubility of Salt X equals the solubility of Salt Y at a temperature between:
10 °C and 20 °C
20 °C and 30 °C
30 °C and 40 °C
40 °C and 50 °C correct
Show the explanation
At 40 °C, Salt X (48 g) is still below Salt Y (57 g), but at 50 °C, Salt X (70 g) is above Salt Y (53 g), so the two curves cross between those two temperatures. In every earlier row Salt Y is far above Salt X.
Example 3Harder
A student measured the solubility of two salts, Salt X and Salt Y. For each trial, the student added salt in small amounts to 100 g of water held at a set temperature, stirring until no more salt would dissolve. The mass of salt that had dissolved at that point, in grams per 100 g of water, was recorded as the solubility of that salt at that temperature. Results are shown in Table 1 and Figure 1.
Water temp (°C)
Salt X solubility (g/100 g water)
Salt Y solubility (g/100 g water)
10
22
74
20
31
68
30
42
62
40
48
57
50
70
53
60
88
49
If the trends in Table 1 continued, then at 70 °C the solubility of Salt X would exceed the solubility of Salt Y by:
less than 20 g
about 25 g
about 39 g
more than 45 g correct
Show the explanation
The gap (Salt X minus Salt Y) grows steadily: it is 17 g at 50 °C and 39 g at 60 °C, so the next step must be well above 39 g. The three smaller values all describe gaps already reached at or below 60 °C.
Example 4Medium
A student measured the solubility of two salts, Salt X and Salt Y. For each trial, the student added salt in small amounts to 100 g of water held at a set temperature, stirring until no more salt would dissolve. The mass of salt that had dissolved at that point, in grams per 100 g of water, was recorded as the solubility of that salt at that temperature. Results are shown in Table 1.
Water temp (°C)
Salt X solubility (g/100 g water)
Salt Y solubility (g/100 g water)
10
22
74
20
31
68
30
42
62
40
48
57
50
70
53
60
88
49
Suppose the student had repeated the procedure for Salt Y at 35 °C. The mass of Salt Y that would have dissolved in 100 g of water would most likely have been:
less than 49 g
between 49 g and 53 g
between 57 g and 62 g correct
greater than 68 g
Show the explanation
Salt Y solubility falls steadily as temperature rises, from 62 g at 30 °C to 57 g at 40 °C, so a value at 35 °C must lie between those two entries. Values below 53 g occur only at 50 °C or higher, and values above 68 g occur only at 10 °C.
Drill all 156 of them
Open the drill inside CruxStudy and it serves data representation questions one at a time, with an explanation after every answer and your accuracy tracked. Free, no account.
CruxStudy is a college admission test prep program by CruxSci. Not affiliated with, or endorsed by, the College Board or ACT, Inc. Example questions are original CruxStudy material.