In Data Sufficiency, generally, a question is followed by two statements. You need to decide whether the information given in any of the statements individually or together is sufficient to get the answer or not. This page here on provides information on How to Solve Data Sufficiency Questions
The best way to understand Data Sufficiency is by going through its solved questions. Reasoning is all about more and more practice. Here are a few solved Questions to help you in a better way.
1.What is Rahul's rank in the class?
I. There are 30 students in the class.
II. There are 5 students who have scored less than Rahul.
Options:
A. if the data in statement I alone are sufficient to answer the question;
B. if the data in statement II alone are sufficient to answer the question;
C. if the data either in I or II alone are sufficient to answer the question;
D. if the data even in both the statement together are not sufficient to answer the question;
E. if the data in both the statements together are needed.
Solution:
Out of 30 students 5 are behind of Rahul, means Rahul's rank is 24th in the class.
Hence both statements are required to solve this.
Correct option: E
2.What day is the fifth of a given month?
I. Tuesday is the last day of the month.
II. The third Monday of the month was eighth.
Options:
A. if the data in statement I alone are sufficient to answer the question;
B. if the data in statement II alone are sufficient to answer the question;
C. if the data either in I or II alone are sufficient to answer the question;
D. if the data even in both the statement together are not sufficient to answer the question;
E. if the data in both the statements together are needed.
Solution:
Statement 2 clearly answers that fifth day is Friday, hence option B is correct.
Correct Option: B
3.When can Rajesh get next flight for Simla from Delhi if it is 7.00 pm?
I. Flights for Simla leave after every 45 minutes, till 9 p.m.
II. Twenty-five minutes ago, one flight has left for Simla.
Options:
A. if the data in statement I alone are sufficient to answer the question;
B. if the data in statement II alone are sufficient to answer the question;
C. if the data either in I or II alone are sufficient to answer the question;
D. if the data even in both the statement together are not sufficient to answer the question;
E. if the data in both the statements together are needed.
Solution:
By reading both the statements, it clearly represents that first flight left before 25 minutes only, hence the next flight will leave by 7.20 which can be identified by having both the options hence, option E is correct.
Correct option: E
Represent The Blood Relation Or Coding-Decoding Problems On Paper To Easily Process It
1.How is Beta related to Chitra?
I. Alpha and Beta are brothers and Chitra and Drishti are sisters.
II. Alpha’s son is Drishti’s brother.
Options:
A. if the data in statement I alone are sufficient to answer the question;
B. if the data in statement II alone are sufficient to answer the question;
C. if the data either in I or II alone are sufficient to answer the question;
D. if the data even in both the statement together are not sufficient to answer the question;
E. if the data in both the statements together are needed.
Solution:
By using the above notations we can draw the below diagram. Alpha, Beta is taken ‘+’ and Chitra, Drishti is taken as ‘-’. It seems that Alpha, Beta belongs to one generation and Chitra, Drishti belongs to another generation.
So, Alpha, Beta is taken in one horizontal row and Chitra, Drishti is taken in another horizontal line. It says that Alpha is Chitra’s father. Father’s brother is an uncle. So, the answer is uncle.
Correct option: E
2.What is the mathematical code for ‘coconut’ in a certain code?
I. The code for ‘give me coconut’ is ‘777’.
II. The code for ‘you can bring coconut for me’ is written as ‘673196’.
Options:
A. I alone is sufficient while II alone is not sufficient
B. II alone is sufficient while I alone is not sufficient
C. Either I or II is sufficient
D. Neither I nor II is sufficient
E. Both I and II are sufficient
Solution:
Statement 1 and 2 both do not contain clear information to answer the code of coconut hence, option D is correct.
Give me coconut =777
You can bring coconut for me 673196
7 is common for coconut/me=? Cannot be determined
Correct Option: D
3.Who among Parul, Query, Tanmay, Vimal, and Monty is exactly in the center when they are in rising order of their heights?
I. Vimal is taller than Query but shorter than Monty.
II. Tanmay is taller than Query and Monty but shorter than Parul.
Options:
A. I alone is sufficient while II alone is not sufficient
B. II alone is sufficient while I alone is not sufficient
C. Either I or II is sufficient
D. Neither I nor II is sufficient
E. Both I and II are sufficient
Solution:
Taller to Smaller->
Parul
Tanmay
Monty
Vimal
Query
Correct option: E
1.On which day in April is Rahul’s birthday?
I. Rahul was born exactly 30 years after his mother’s born.
II. His mother will be 50 years 5 months and 9 days on August 20 this year.
Options:
A. if the data in statement I alone are sufficient to answer the question;
B. if the data in statement II alone are sufficient to answer the question;
C. if the data either in I or II alone are sufficient to answer the question;
D. if the data even in both the statement together are not sufficient to answer the question;
E. if the data in both the statements together are needed.
Solution:
Statement 1 and 2 both contain information to answer Rahul’s birthday hence, option E is correct.
Correct option: E
2.How many guests saw the trade fair yesterday?
I. Up to three persons can enter having one entry pass with him/her.
II. Total, 333 passes were sold yesterday.
Options:
A. I alone is sufficient while II alone is not sufficient
B. II alone is sufficient while I alone is not sufficient
C. Either I or II is sufficient
D. Neither I nor II is sufficient
E. Both I and II are sufficient
Solution:
Statement 1 and 2 both do not contain clear information to answer the number of guests, who saw the fair hence, option D is correct.
Correct Option: D
3.On Tuesday how many milk packets were sold?
I. It was 20% more than the milk packets sold on the earlier day i.e., Monday.
II. Every alternate visitor to the shop purchased the milk packets and 2500 visitors were there on Monday.
Options:
A. I alone is sufficient while II alone is not sufficient
B. II alone is sufficient while I alone is not sufficient
C. Either I or II is sufficient
D. Neither I nor II is sufficient
E. Both I and II are sufficient
Solution:
Statement 1 and 2 both contains information to answer the number of milk packets sold i.e. 1500 hence, option E is correct.
Correct option: E
1.Out of the 100 animals in the Omaha zoo, how many are lions?
I. 60 of 100 are newly born elephants (Calf).
II. 20 animals out of 40 are not elephant but a lion.
Options:
A. if the data in statement I alone are sufficient to answer the question;
B. if the data in statement II alone are sufficient to answer the question;
C. if the data either in I or II alone are sufficient to answer the question;
D. if the data even in both the statement together are not sufficient to answer the question;
E. if the data in both the statements together are needed.
Solution:
As we see in the Venn diagram, statement A gives information about 60 baby elephants out of a total of 100 animals. Further statement B talks about 20 animals that are a lion but does not give information about the remaining 20. They may be a lion or any other animal also. Hence both the statements are not capable to provide an exact number of lions. Thus option D is correct.
Correct option: D
2.There are 60 children admitted to a Music Academy. Some children can play only Guitar and some can play only Sitar. How many children can only play Sitar?
I. 15 children can play both Guitar and Sitar
II. The total number of children who can play Guitar is 27
Options:
A. I alone is sufficient while II alone is not sufficient
B. II alone is sufficient while I alone is not sufficient
C. Either I or II is sufficient
D. Neither I nor II is sufficient
E. Both I and II are sufficient
Solution:
Statement 1 gives information about common students for Guitar and Sitar. Now, statement 2 talks about the total number of children who can play Guitar is 27. Thus by using both the statements, we can conclude that:
27 – 15 = 12 children can only play Guitar; 60 – 12 = 48 children can play Sitar
Student for only sitar=48 – 15 = 33
Hence 33 students can only play Sitar which comes from both the statements. Hence option E is correct.
Correct Option: E