How to Read Multi-Source Reasoning Problems, Part 1
Given that Integrated Reasoning may become more important for those who want to go into consulting or banking, let’s take a look at a Multi-Source Reasoning (MSR) problem!
In this first part, we’re going to take a look at how to read and take notes on the MSR text. In the next article, we’ll do a problem that goes with the text. This MSR is from the free GMATPrep test, so if you have not yet taken GMATPrep, don’t read this article yet! Put it away and come back to it after you’ve seen the problem yourself.
MSRs appear as three tabs of information. I can’t format things into tabs here, so I’ll just show it all to you one after the other. You have about 2.5 minutes per question on IR. This MSR has a total of 3 associated questions, but I’m only giving you one in this article. Spend about 2 to 2.5 minutes on the read-through, leaving yourself about 1.5 to 2 minutes to spend on each question.
Tab 1
“An archaeological team has been excavating three ancient village sites—Barras, Agna, and Cussaia—looking in particular at kitchen waste dumps as a way to understand the villages’ dietary patterns and trading relationships. What follows are brief summaries of their findings.
“Barras: The best data come from stratified finds in this oceanside village, which was inhabited from AD 600 to 1300 and was the only one of the three villages to produce seafood, its main dietary item. Though Barras residents hunted on land and raised crops, this provided relatively small amounts of food. As Barras’s overall prosperity rose, there was more food available per person, and its population increased from an average of 100 residents in the AD 600s to 400 residents in the AD 1000s to 600 residents in the AD 1200s.
“Agna: Agna was established in an inland forest around AD 800 and its residents mainly hunted but also ate considerable amounts of fruit, nuts, and other forest-vegetable products. They also traded meat to Barras for other goods. With no open fields, Agna grew no grain.
“Cussaia: Predating Barras, Cussaia depended heavily on raising grain crops and eventually obtained seafood and meat via trade. It traded directly only with Barras, because a mountain range separated it from Agna, though some products may have been traded between Agna and Cussaia via Barras.
“Additionally, there is no evidence that any other village traded with Barras, Agna, or Cussaia prior to AD 1300.”
—
Tab 2
“Barras: Percentages, by Estimated Weight, of Dietary Items Consumed per Person per Month”
Century Seafood
Meat
Grains
Other
600s 65%
10%
10%
15%
700s 65%
10%
15%
10%
800s 60%
15%
15%
10%
900s 45%
30%
12%
13%
1000s 45%
30%
12%
13%
1100s 60%
10%
20%
10%
1200s 55%
25%
10%
10%
—
Tab 3
“Barras, Agna: Estimated Average Monthly Meat and Seafood Consumption (lb per 4-Person Family)”
Century Barras
Agna
Seafood
Meat
Seafood
Meat
600s 240
37
not applicable
not applicable
700s 250
38
not applicable
not applicable
800s 275
70
60
240
900s 258
172
66
180
1000s 240
160
66
186
1100s 275
45
8
240
1200s 265
120
45
240
—
That’s a lot to read through in only 2 minutes or so. The key is to be able to divide the info into three categories:
(1) Important and I need to understand right now
(2) Important but I can come back to it later, when I’m doing the questions
(3) Not that important (but I can still come back if necessary)
How can you possibly know what likely will and will not be important? There are some good clues; your job is to learn how to use them.
The first tab will almost always contain text providing the main storyline. The second and third tabs may contain additional text, or charts or graphs, or some combination of the two.
In general, it’s a good idea to look through the tabs in order. As expected, the first tab does provide the background for the whole story, so dive in.
The opening sentence indicates the key focus: the archaeologists used kitchen waste dumps to understand dietary patterns and trading relationships. Great! Jot down info about dietary patterns and trading relationships; pay less attention to other info.
Hmm. Barras, Agna, and Cussaia each have their own paragraphs. First, abbreviate using the letters B, A, and C. Second, these paragraphs contain quite a bit of information, but don’t bother to note down that the best data came from B or that it was an oceanside village. Don’t note that A was an inland forest. Why? These don’t directly address the dietary patterns or trading relationships. Note that B did experience a population increase, but ignore the details; you can go back for them later if you need them.
You can also ignore the last sentence of the first tab (“there is no evidence that any other village traded with B, A, or C prior to AD 1300”). It’s there just to let us know that we can disregard the idea that some other culture or village might have affected trade. This is the equivalent, on a math problem, of giving 1/x and saying that x does not equal zero.
One good set of notes for this MSR might look something like this (everyone’s notes will be a bit different, of course):
T1
B: Seafood. Some hunt, crops. Pop >>.
A: Hunt and gather. Trade meat w/B. No grain.
C: Grain. Got fish, meat via trade with B.
T2: B % food type per month by century
T3: B, A: meat, fish lb eaten per 4-people by century
Obviously, we’re not going to write out the data from the 2nd and 3rd tabs; just note what kind of information is found in each tab.
Okay, are you ready to try a problem? I’ll tell you what: I’ll give you one here, but I’m not going to give you the solution or explanation until the second part of the article. You can go look up the solution, of course. If you run into trouble, though, I encourage you to spend some time wrestling with it and trying to figure it out yourself. You’ll learn a lot more in the end.
Here you go. Give yourself about 1.5 minutes to answer.
“Based on the information in the passage and tables, it can be determined that the average monthly meat consumption, in pounds, by the residents of Barras in the AD 1000s was which of the following?
“(A) 9,600
“(B) 10,000
“(C) 16,000
“(D) 17,400
“(E) 18,000”
Read the second half for the solution and a discussion of the problem. (I might also give you a second problem for this same MSR…)
Key Takeaways for Reading MSR Problems
(1) The first tab is going to set context for you, but it’s also going to include a lot of unnecessary information. How to know what’s important? Pay attention to the first few sentences, which will tell you the theme of the coming information. Take notes on anything that fits that key theme and ignore the rest.
(2) Don’t write down numbers! Write down what the numbers represent and where to find them again. For example, note that the B paragraph in tab 1 gives data on population increases. Note the kind of information contained in the tables in tabs 2 and 3.
(3) Expect to spend about 2 to 2.5 minutes overall for your initial read-through of the tabs. That will leave you with about 1.5 to 2 minutes per question (most MSRs have a total of 3 questions).
* GMATPrep® questions courtesy of the Graduate Management Admissions Council. Usage of this question does not imply endorsement by GMAC