Data Sufficiency

One of the standard ways to test a person’s analytical skills is through Data sufficiency. We will be looking at the subject of Data sufficiency as a whole and its importance to us as reasoning beings.

What is Data Sufficiency?

Data sufficiency, by its name, is a process by which we determine if a piece of information given to us is useful for our purposes.

It is used to verify a piece of the given information, especially if it is enough to answer a particular question.

For example, a data sufficiency question typically involves a question and two groups of information given. Then, it’s the work of the examiner to solve the problem using the groups of information given.

Note: No guesswork is allowed in Data Sufficiency. Only one answer can be gotten from every question. 

Data sufficiency is under Verbal and Logical Reasoning and can also be derived from Quantitative Reasoning.

Types of Data Sufficiency

There are various types of data sufficiency questions; all of which differ by subject matter related to the question.

1. Sequence

This type of data sufficiency question deals with the order that things or people are arranged systematically. It can also be called Order/Ranking and here data is provided on sequences where the candidate involved is required to find out if the information given is adequate to attempt the given question.

1. Blood relation

A question will be given here which typically involves the familial ties of hypothetical people. The problem is then to find out using the information given if it is true or not.

1. Direction and Distance

This type of data sufficiency deals with the information provided about the specific locations of people; and/or the distance traveled by them; all of which is required for the candidate to find out which statement given is sufficient to answer the question.

1. Coding

Coding data sufficiency questions formulate codes from words or letters; expecting candidates to unravel the codes by the given set of information from the problem.

1. Seating Arrangement 

Data on different seating arrangements will be provided and the candidate is expected to evaluate for the most sufficient piece of information to get to the problem.

Irrespective of whether it is a Linear arrangement or a Circular arrangement, the concept remains the same as before.

1. Puzzle Tests

This type of data sufficiency examines the candidates’ ability to see and identify solutions to puzzles from previously given information.

1. Calendar Problems

Also termed as Scheduling, this part of Data sufficiency deals with dates, months and years, of which data in these will be sent and evaluations will be made on the questions given based on a set of information in question.

The Logic Behind Data Sufficiency Questions

Data sufficiency questions are forgotten from fields such as Verbal and Quantitative Reasoning, Data Interpretation and Mathematics. 

The correct methods to answering data sufficiency questions are diverse, but a general view on all of them is given below:

1. Read and carefully review all the instructions given in that question. This will help you to get a grip on whatever was asked, though it might seem overly complicated while reading.

1. Do not assume the final answer. It is preferred if you go through the statements given, check both of them and then use them to get the required answer.

Sample Data Sufficiency Questions

The list below contains some data sufficiency problems and how they are reasoned.

Question: Who is R’s partner in a game of cards involving platers P, Q, R and S?

(I) P is sitting opposite to S

(II) Q is sitting to the right of P and left of S

Solution:

This is under seating arrangement. From the question, it can be seen from both of the given statements(set of information) that P is sitting opposite to S and it is the seat partner to A.

Question: If City A and City E are in a straight line and the distance between A and C is equal in distance between F and E then find out City A is in which direction concerning City E.

(I) A is the north of F, which is to the west of C

(II) A is to the northwest of C

(III) E is to the northwest of F

Solution:

This question is under Distance. 

To get the solution, sketching all the directions mentioned in the statements onto a piece of paper will reveal that only statements I and III are sufficient to get the final answer.

Question: If x is a positive integer, is x > 15?

(I) x > 10

(2) x < 14

1.  1 only is enough but statement 2 only is not enough.
2. 2 only is enough  but statement 1 only is not enough
3. Either 1 or 2 only is enough 
4. 1 and 2 put together are not enough to answer the question 

Solution:

For this problem, it can be inferred that since x is greater than 15, statement 1 isn’t sufficient enough since x is greater than 10(which is lesser than 15).

However, statement 2 is more adequate to deduce the value of x since it is closer to the upper limit of x and in that case, option B is correct.

Exams That Use Data Sufficiency

Data sufficiency reasoning is used to test analytical and critical thinking. Hence, its use in education cannot be overemphasized. The following are exams that make use of data sufficiency:

• GMAT
• Banking exams(Clerks)
• RRB
• UPSC
• SSC

Conclusion

Data sufficiency reasoning is vital to professionals that require critical thinking. Thus, the understanding of data sufficiency is needed to understand the subject matter that is being discussed in such fields.