In some cases you’ll want to eliminate answer choices that create mistakes. This is an especially good strategy for ACT English and Math, as those two sections focus on mistakes in the writing and calculation processes. In other cases, you’ll want to rule out answer choices that aren’t supported in the information the test gives you. This approach is key to ACT Reading and ACT Science, which primarily test passage comprehension and your ability to interpret data. In this post, we’ll look at this second strategy as it’s used in the ACT Science section.
Below is a sample ACT Science passage. Like many Science passages on the actual exam, this reading comes with a graph. The graph is not perfectly ACT-like, because it’s in color, but the infographic does have the same level of complexity as a typical ACT graph and it also covers a very ACT-like general science subject. I actually got this visual from the personal homepage of Dr. Kelly Cassidy, an animal biology scientist for Washington State University. The passage and question are original creations just for the Magoosh HS Blog.
The lifespan of domesticated canines varies greatly from breed to breed. Veterinary scientists have detected some potential correlation between the average weight of a breed of dog and that breed’s longevity. Figure 1 shows different weight classes of dogs, the number of dog breeds that fall into that weight class, and the number of breeds in each weight category and lifespan grouping.
Assuming the data in the graph is accurate, what is true of dog breeds with an average weight of 40 pounds or less?
A) They represent the most common weight class, in terms of number of breeds.
B) They have the lowest median lifespan.
C) Breeds in this group live longer than any breed that weighs 80 pounds or more.
D) All breeds within this group live 10-14 years.
This is a fairly complicated chart, as bar graphs go. There are two variables with multiple subcategories running along the x-axis, weight class (7 subcategories) and average lifespan (10 subcategories). Both of these x-axis variables interact with each other in complex ways. Moreover, they also both have a relationship with an additional y-axis category, the number of breeds in each weight and lifespan grouping.
This is where it’s useful to check each answer choice and see if it’s supported by the info in the passage/graphic. By methodically employing this strategy, you can cut through the complexity of the information and reach the correct answer choice.
A looks correct at a glance. It does seem like there are more breeds of dog that weigh 40 pounds or under, compared to the breed count of other weight classes. Now, you could carefully look at each colored bar on the graph to double check A down to the finest details of the number of dogs in the >40 lb. and <40 lb. weight classes. However, you’ll likely save time by simply spot checking the other answers to see if you can confirm A as true by process of elimination.
B appears to not be correct. There are a visibly large number of less-than-20 and 20-40 pound dogs in the upper levels of lifespan, with a lot of length for blue and pink bars in the age brackets between 11 and 15 years old. Again, you could carefully double check, but it’s probably best to move on and check the other choices for accuracy first.
C is easy to check with complete accuracy, because it’s an absolute statement. To see if all dog breeds that weigh forty pounds or less live longer than all breeds above the 80 pound average, simply scan for the pink and blue bars in the <20 lb. and 20-40 lb. categories, and then see if the light orange, dark orange, or red bars show a group of 80 + pound dog breeds outliving a different group of smaller 40-pound-or-less dogs. Reading the graph from left to right, you can see some heavier dogs outliving other smaller breeds right away: the 7-8 year lifespan section consists entirely of dogs weighing a hundred pounds or more, while the shorter 6-7 year lifespan level just to the left shows one 20-40 pound breed.
D again is an absolute statement. To know whether all dogs in the 40-or-less weight class live 10-14 years, you just need to look outside those lifespan categories. You can see five breeds in this lower-weight class in the 14-15 year category, and six breeds of this these smaller dogs with 9-10 year and below lifespans. So D can’t be true either.
This leaves you with answer choice A being probably true, answer choice B being probably false, and the third and fourth answers completely eliminated. If you have time, you could comb through the graph carefully to double-check A and B, but A is probably a very safe bet (and is in fact the correct answer).