The key to scoring well in the DI section entails practice, practice and more practice; but most importantly, the right kind of practice.
When you look at a question in the CAT paper, you should be able to relate to it instantly. Questions which make their appearance in the DI section can be categorized easily into a particular type; for exampleà Game based, Venn diagram based, Percentage based, Allegation based etc.
In this tutorial, we will focus on 4 different types and approaches to solving some typical DI questions. You will learn how to use unique techniques like the “Reverse Gear approach” and “Lateral thinking” to your advantage, and solve tough DI questions in no time at all!
TYPE 1) GAMING IN THE DATA INTERPRETATION SECTION
Game Based questions that have made their appearance in the Data Interpretation section are usually difficult to solve. However, once you get familiar with these questions, you can frame a strategy to attempt such questions making them relatively easy to solve. Game Based questions, which fall into the category of Mathematical reasoning, are based on the score lines in a game; positive or negative. Once you get the result of a particular match, the key point is to balance the score line based on the result you have obtained.
To understand what I am saying better, let us look at a typical game based caselet
Answer the questions based on the information given below
The following table gives the information about Quarter final stages of the UEFA Champions league. There are 4 teams in Group A which are AC Milan, Barcelona, Chelsea and Deportivo.
Each team played every other team exactly once. Some data is missing in the table. 3 points are awarded for a win and 1 point for a draw. Top two teams will qualify for the semifinal stage. Top two teams are decided , first by the points scored; if points are equal then team with better goal difference will qualify( goal difference = goals for- goals against). If goal difference is also equal then team which scored more number of goals will qualify.
Team | Matches | Wins | Losses | Draw | Goals for | Goals against |
AC Milan | 3 | | 1 | 0 | 4 |
1 |
Barcelona | 3 | | | 1 | 6 | 3 |
Chelsea | 3 | | 0 | | 4 | 2 |
Deportivo | 3 | | | | 1 |
|
1) What is the result of the match Chelsea against Deportivo?
a) 2-1 b) 1-0 c) 1-1 d) none of these
2) Which team topped group A?
a) AC Milan b) Chelsea c) Barcelona d) a or b
3) How many goals were scored against Deportivo?
a) 2 b) 5 c) 8 d) none of these
4) Which of the following matches ended in a draw?
a) Barcelona-Chelsea b) Barcelona- Deportivo
c) Chelsea- Deportivo d) Indeterminable
SOLUTION
Clearly, there are 6 matches played totally in Group A, where each team plays against every other team exactly once. This can be written as
A X B
A X C,
A X D,
B X C,
B X D,
C X D, Where A, B, C, D stand for AC Milan, Barcelona, Chelsea and Deportivo respectively
The first point in the table we need to observe is that A is losing 1 match and C does not lose any match. This means that in the match A X C, A is the loser and C is the winner. Also, since the number of goals against A are 1, we can also decide the score line of this match as 0-A and 1-C. The balance score line for A is thus, 4-0 and the balance score line for C is 3-2. We can also conclude that A wins its other two matches against B and D as it has zero draws and only 1 loss.
Now consider the remaining two matches of B, one is a draw (given) and the other B must win to have an overall positive score line of (6-3). B can’t win against C as C is not losing any match. So we can conclude that B is winning against D and the match between B and C is ending in a draw.
The next step is deciding the score lines.
Now the possible score sets in matches C X B and C X D are:
1-0 1-1 3-2
2-2 2-1 0-0
Not possible. If C-D match Not possible, because C-D match can not end in 3-2
is ending in 1-0 then D has to as D is scoring just 1 goal.
score 1 goal against A which is
not possible as the only goal against
A is scored by C as discussed above.
Now B’s balance score line is 5-2 out of which 0 goals are against A (total number of goals against A is 1 which is given by C), therefore against D; B scores 5 goals.
The total number of goals for (GF) should be equal to the total number of goals against(GA); therefore, total number of goals against D can be calculated as 9, out of which 5 goals are scored by B and the remaining 4 goals are scored by A and C together.
Number of Goals for D is given as 1, which will be against C (because C has 2 goals against it out of which 1 goal is from B and 0 from A). The score for A X B thus becomes 2-0 and the score for the match A X D is 2-0 again. There can only be 6 different score lines. We can now fit in the score lines for the every match.
A X B= 2 X 0
A X C= 0 X 1
A X D= 2 X 0
B X C= 1 X 1
B X D= 5 X 0
C X D= 2 X 1. Now all the questions can be answered. Answers are option (a), option (b), option (d) and option (a)
Thus we see that in game based questions we need to connect different points to conclude a new point. What you must look for in a game based question is a specification that connects different point or conditions. In this question that specification is the score line. You need to keep the score lines of each team in mind and before concluding the result in a match you should make sure that it is satisfying all the score lines. In some other question that specification can simply be the number of matches played against different teams.
STRATEGIES:
1) In this question, it is not necessary to find all the score lines to answer 3 of the 4 questions. Always go through the questions before finding out all the score lines.
The drawn match (B-C), the number of goals against D and the team that tops group A can be found without consuming much time
2) Even if you decide to leave this caselet, you should attempt question number 3; as to answer this question all you need to know is that the number of goals scored= number of goals against.