## Data Sufficiency

#### Introduction

CAT test writers use data sufficiency questions to test your ability to "reason quantitatively." This stands in sharp contrast to the problem solving section, which is designed to test how well you manipulate numbers. If you find yourself doing a lot of number crunching on the data sufficiency questions, you are doing something wrong.

#### Math Concepts You Should Know

The data sufficiency questions cover math that nearly any college-bound high school student will know. In addition to basic arithmetic, you can expect questions testing your knowledge of averages, fractions, decimals, algebra, factoring, and basic principles of geometry such as triangles, circles, and how to determine the areas and volumes of simple geometric shapes.

CAT data sufficiency questions will all have the exact same answer choices. Memorize these answer choices before you take the exam. It will help you better utilize your time in the quantitative section. The answer choices are summarized below as you will see them on the CAT exam.

1. Statement 1 alone is sufficient but statement 2 alone is not sufficient to answer the question asked.
2. Statement 2 alone is sufficient but statement 1 alone is not sufficient to answer the question asked.
3. Both statements 1 and 2 together are sufficient to answer the question but neither statement is sufficient alone.
4. Each statement alone is sufficient to answer the question.

#### Use Process of Elimination

If statement 1 is insufficient, then choices A and D can immediately be eliminated.

Similarly, if statement 2 is insufficient, then choices B and D can immediately be eliminated.

If either statement 1 or 2 is sufficient on its own, then choices C and E can be eliminated.

#### A Simple 4 Step Process for Answering These Questions

Many test takers make the mistake of not arming themselves with a systematic method for analyzing the answer choices for these questions. Overlooking even one step in the process outlined below can make a big difference in the final quantitative score you will be reporting to your selected business schools.

1.) Study the questions carefully. The questions generally ask for one of 3 things: 1) a specific value, 2) a range of numbers, or 3) a true/false value. Make sure you know what the question is asking.

2.) Determine what information is needed to solve the problem. This will, obviously, vary depending on what type of question is being asked. For example, to determine the area of a circle, you need to know the circle's diameter, radius, or circumference. Whether or not statements 1 and/or 2 provide that information will determine which answer you choose for a data sufficiency question about the area of a circle.

3.) Look at each of the two statements independently of the other. Follow the process of elimination rules covered above to consider each statement individually.

4.) If step 3 did not produce an answer, then combine the two statements. If the two statements combined can answer the question, then the answer choice is C. Otherwise, E.

#### Data Sufficiency Tips and Strategies

Use only the information given in the questions. The CAT seeks to measure your ability to distinguish facts from careless assumptions. Do not rely on a visual assessment of a diagram accompanying a geometry question to determine angle sizes, parallel lines, etc. In addition, do not carry any information over from one question to the next. Each question in the data sufficiency section of the CAT stands on its own. You can count on seeing at least a few questions where a wrong answer choice tries to capitalize on this common fallacy.

Do not get bogged down with complicated or lengthy calculations. As we stated before, these questions are designed to test your ability to think conceptually, not to solve math problems.

Use process of elimination. This CAT section lends itself perfectly to using the process of elimination. If time becomes an issue, you can always look at the 2 statements in either order. Remember, the order you analyze the two statements in doesn't matter, so long as you begin by looking at them individually. If you find statement 1 confusing, you can save time by skipping to statement 2 and seeing whether it can help you eliminate incorrect answer choices.

Be on the lookout for statements that tell you the same thing in different words. When the 2 statements convey the same exact information, you will know, through process of elimination, that the correct answer choice is either D or E. A favorite ploy of CAT testers is to mix ratios and percentages. Here is an example where Statement 2 simply states backwards the exact same information provided by Statement 1.

1. x is 50% of y
2. the ratio of y:x is 2:1

Make real-world assumptions where necessary. You must assume that, in certain abstract questions such as "What is the value of x?", that x might be a fraction and/or a negative number.

Practice, practice, practice. The more time you spend practicing data sufficiency questions, the better able you will be to internalize the tips and strategies given above. You will also become very comfortable with the type of questions from this portion of the test, and will quickly realize if there are any math areas, such as geometry or algebra where you need to brush up your skills. When it comes time to sit for the CAT, you will want to know key math formulas and data relationships off the top of your head.

## Logical Reasoning

Logical Reasoning is always the toughest part of CAT. In CAT LR questions usually comes with 2/3 bits . A paragraph is given with full of information followed by 2/3 questions. You have to read it and use your logic to answer the questions. In 3 sections CAT paper there is no special section on LR but one can expect LR questions to be present in any section.

The main idea behind LR is to is use the information and preconditions to make a conclusion

Most problems give a variety of conditions and you must use an "if"-"then" approach. It's important that you read the whole problem, and choose the best hint or clue before starting to solve the problem. When practicing logic with reasoning making a chart or drawing a picture are good strategies. Before starting any LR problem it s advised to keep few points in mind.

Important Tips for Logical Reasoning

Before you try to answer a few sample questions, here are some general test-taking tips that should help you with the Logical Reasoning section.

1. Study the question carefully. A brief explanation of why each choice is correct or incorrect follows each practice question. If you understand this reasoning for the practice items, you will do well on the actual assessment.

2. NEVER assume or use any information that the question fails to give you. This is NOT an assessment of how much you know about economics in general! Consider ONLY the information given in each reading passage when choosing among the alternative responses.

3. Read both the factual passage and the sentence completion instruction carefully. Both must be considered in making your choice.

4. Be sure to read all the response choices carefully before choosing one.

5. In questions that ask you to select a valid conclusion, always choose the one conclusion that must definitely follow from the information you are given. In questions that ask you to find the invalid alternative, choose the one conclusion that does not definitely follow from the information.

6. Pay special attention to words like "all," "some," or "none" when you read the factual information each question gives you. Other qualifying words such as "other than," "only" or "unless" are important, too. These words can play a critical part in precisely specifying the facts to be used in your reasoning.

7. Pay attention to negative prefixes also, such as non-, un-, or dis-. These can be crucial to specifying the basic facts in the paragraph.

8. "Test-taking" courses or your college instructors may have advised you to avoid any response choices that contain the quantifiers "all" or "none." In both the practice questions here and in the actual economist assessment, these words are NOT signs of incorrect response choices. They will appear in both correct and incorrect response choices.

9. Pay close attention to the word "ONLY" and to the phrase "IF AND ONLY IF." Saying "The door will open IF AND ONLY IF both keys are used" sets up a highly specific condition that must be met. There is exactly one way to open the door-you must use both keys. By contrast, if the sentence says, "The door will open if the key is used," there may be several ways to open the door besides by using the key.

10. The questions in the assessment will vary in difficulty level, and difficult questions will be mixed in with easier ones throughout the assessment. When you encounter a question that is difficult for you, try drawing diagrams or other schematic notes on the "scratch" paper provided to support and confirm your thought processes. Also, bear in mind that you can stop working on a difficult question temporarily and return to it later.

### Example1

Q. 1 to 4 are based on the following information: - Ghosh Babuâ€™s new interest is psychology. He has identified various personality patterns and given them names. These personality patterns are inter-related as follows: - All Alessandras, Belissimas, Cassandras, Desdemonas, Elissimas and Firdauses are Queens. - All Alessandras are Belissimas. - No Belissima that is not an Alessandra is a Firdaus. - Some Cassandras are Alessandras. - All Desdemonas are Cassandras. - Some Cassandras are not Belissimas. - No Desdemona is an Alessandra. - All Queens and only Queens that are neither Belissimas nor Cassandras are Elissimas. 1. Which of the following is true? (1) All Firdauses are Alessandras. (2) Some Firdauses are Alessandras. (3) All Firdauses are either Alessandras, Cassandras or Elissimas. (4) Some Firdauses are Cassandras. 2. Which of the following is not true? (1) No Desdemonas are Belissimas. (2) Some Belissimas are Desdemonas. (3) Some Firdauses are both Belissimas and Cassandras. (4) Some Queens are neither Belissimas nor Elissimas. 3. Which of the following cannot be said to be true or false? I. No Belissima or Cassandra is an Elissima. II. Some Cassandras are Belissimas but not Alessandras. III. No Belissima is both an Alessandra and a Desdemona. (1) I only (2) II only (3) III only (4) I & II 4. Peter is not a Belissima, therefore, (1) Peter is an Elissima (2) If Peter is a Queen, he is an Elissima or Cassandra. (3) If Peter is not an Elissima, he is a Cassandra. (4) None of the above ANSWERS: 1. (3) 2. (1) 3. (2) 4. (2)

### Example2

DIRECTIONS for questions 5 to 7: Answer the following questions based on the passage below. A group of three or four has to be selected from seven persons. Among the seven are two women, Fiza and Kavita, and five men: Ram, Shyam, David, Peter and Rahim. Ram would not like to be in the group if Shyam is also selected. Shyam and Rahim want to be selected together in the group. Kavita would like to be in the group only if David is also there. David, if selected, would not like Peter in the group. Ram would like to be in the group only if Peter is also there. David insists that Fiza be selected in case he is there in the group. 5. Which of the following statements is true? a. Kavita and Ram can be part of a group of four. b. A group of four can have two women. c. A group of four can have all four men. d. None of the above 6. Which of the following is a feasible group of four? a. Ram, Peter, Fiza, Rahim b. Shyam, Rahim, Kavita, David c. Shyam, Rahim, Fiza, David d. Fiza, David, Ram, Peter 7. Which of the following is a feasible group of three? a. David, Ram, Rahim b. Peter, Shyam, Rahim c. Kavita, David, Shyam d. Fiza, David, Ram Answers: 5. d The group of 4 cannot be made, except S + R + F + D. 6. c From the above 7. b In all the other choices we have D, who insist that F be with him.

### Example3

Directions for 8 â€“ 10: Mr. Doubt fire has an unique way of attempting the question paper having 50 Qs. He starts from question 1 and attempts all questions which are terms of the A. P with a common difference of 3 in the forward direction and 3 in the reverse direction. If he reaches a stage when he cannot attempt any more question he starts in the reverse direction with the first unanswered question. He repeats the same process and when he reaches a stage when he canâ€™t process any further, he reverses his direction again starting with the first unanswered question 8. Which is the 20th question he answers? (A) 50 (b) 48 (c) 47 (d) 44 9. Which is the last question that he answers if he attempts all the 50 questions? (a) 50 (b) 49 (c) 48 (d) 3 10. How many times does he reverse his direction? (a) 3 (b) 4 (c) 5 (d) 6 ANSWERS 8. (d) 9. (b) 10. (a)

## Data Interpretation

What is DATA? Data is a plural of datum, which is originally a Latin noun meaning "something given." Today, data is used in English both as a plural noun meaning "facts or pieces of information" and as a singular mass noun meaning "information". Information refers to data being arranged and presented in a systematic or an organize form, so that some useful inferences can be drawn from the same. By data we generally mean quantities, figures, statistics, relating to any event.
What is DATA INTERPRETATION? Data Interpretation is the extraction of maximum information from a given set of data or information. The data can be presented either in the form of a table or a bar chart or a pie chart or a line graph or as a combination of one of these formats. In CAT there is a separate section for DI & DS. In past history DI section used to consist of 5-6 sets of data followed by 5-6 easy but lengthy calculation based questions on each set. But the trend of DI section has changed a lot in last couple of years now the questions are of more logical requiring less calculation. In the beginning one should try to get familiarize with all data formats and solve easy questions based on single data/graph. But In real CAT questions are usually asked on combinational graph. Before starting DI section one should be very comfortable with numbers, calculations, fractions and percentages. It helps in reducing the time required for solving the questions. To begin with, you should know how to interpret various data formats. Tables, line graphs, bar graphs, pie charts, three dimensional graphs, flow diagrams and cumulative frequency tables are some of the data formats that have featured in CAT over the years. Before moving to different chapters read the following 5 tips on DI @ http://www.cat4mba.com/node/150 Go through all the chapters carefully. Solve the questions based on simple logic. After completing all the chapters try to solve the questions in question bank and then try all the FLTs.