Tips to Solve Data Sufficiency Questions in Reasoning

About Data Sufficiency:

• These type of questions consists of problems on any reasoning topics like blood relation, coding-decoding, direction test, ranking, seating arrangement, etc. followed by statements containing clues to solve the question
• The candidates are supposed to find out which of the given statements is or are sufficient to solve the given question
• This section tests the candidate’s efficiency to determine the information necessary to solve the given problem
• We have to make sure whether the question can be solved with the help of information provided in the 1^ststatement or 2^nd statement or together in the 1^st and the 2^nd statement
• We are not supposed to assume anything beyond the information given in the question and the following statements

Example Questions:

DIRECTIONS

Answer (1) if the data in statement I alone is sufficient to answer the question, while the data in statement II alone are not sufficient to answer the question

Answer (2) if the data in statement II alone is sufficient to answer the question, while the data in statement I alone are not sufficient to answer the question

Answer (3) if the data either in statement I alone or in statement II alone are sufficient to answer the question

Answer (4) if the data even in statement I and II together are not sufficient to answer the question

Answer (5) if the data in both statement I and II together are necessary to answer the question

QUESTION 1

The Chairman of a big company visits one department on Monday of every week expect for the Monday of 3^rd week of every month. When did he visit the Purchase department?

Statement:

1. He visited Accounts department in the 2^ndweek of September after having visited Purchase department on the earlier occasion
2. He had visited Purchase department immediately after visiting Stores department but before visiting Accounts department

Solution

From statement I alone we can deduce that the chairman visited the Purchase department on Monday of the 1^st week of September

From statement II alone we cannot determine the time of visit of any of the departments. Therefore this statement is not sufficient enough to answer the question

Therefore, statement I alone is sufficient to answer the question, while the data in statement II alone are not sufficient to answer the question

Hence Answer: (1)

QUESTION 2

P, Q, R, S and T are sitting around a circular table facing towards the centre. Who is 2^nd to the right of P?

Statement:

1. R is to the immediate left of T and 2^nd to the right of S
2. Q is to the immediate right of S and 3^rd to the left of P

Solution

From statement I alone we cannot deduce the arrangements

Therefore, the 2^nd position to the right of P can be occupied by either Q or T. It cannot be determined by statement I alone

From statement II alone we can come to the following conclusions

Here the 2^nd position to the right of P can be clearly determined as Q

Therefore, statement II alone is sufficient to answer the question, while the data in statement I alone are not sufficient to answer the question

Hence Answer: (2)

QUESTION 3

In a certain code language, ‘2 9 7’ means ‘tie clip button’. Which number means ‘button’ in that language?

Statement:

1. In the same code language, ‘9 2 6’ means ‘clip your tie’
2. In the same language, ‘1 7 5’ means ‘hole and button’

Solution

From statement I alone we can deduce the common words between the question and this statement are ‘tie’ and ‘clip’ and the common codes are ‘2’ and ‘9’. So, ‘2’ and ‘9’ are codes for tie and clip. Therefore the code for ‘button’ is ‘7’

From statement II alone we can see that the word ‘button’ is common between the question and statement II. Similarly ‘7’ is the common code between them. Therefore, ‘button’ is ‘7’

Therefore, statement I alone or in statement II alone are sufficient to answer the question

Hence Answer: (3)

QUESTION 4

Among A, B, C, D and E, who earns more than only the least earner among them?

Statement:

1. B earns more than A and D but less than only C
2. A earns more than D who earns less than E

Therefore either E or A earns more than the least earner D and we don’t have any other clue to determine which one of them is the exact answer

Therefore, data even in statement I and II together are not sufficient to answer the question

Hence Answer: (4)

QUESTION 5

How is P related to Q?

Statement:

1. R’s sister S has married P’s brother T, who is the only son of his parents
2. Q is the only daughter of T and S

Solution

From statement I alone we know that T is P’s brother and S’s husband. Since T is the only son of his parents, P is T’s sister
From statement II alone we can understand that Q is T’s daughter
Now considering statements I and II together, we can conclude that P is the sister of Q’s father i.e., P is Q’s aunt
Here answer cannot be found using one statement alone.
Therefore, data in both statements I and II together are necessary to answer the question
Hence Answer: (5)