Item contains a Question followed by two Statements. Answer each item using the following instructions : 

Question: Can the value of (x + y) be determined uniquely? 

Statement I: (x + y)4 = 256.  

Statement II: (x + y)3 < 16. 

This question was previously asked in
CDS Elementary Mathematics 16 April 2023 Official Paper
View all CDS Papers >
  1. Choose this option if the Question can be answered by one of the Statements alone but not by the other.  
  2. Choose this option if the Question can be answered by either Statement alone.
  3. Choose this option if the Question can be answered by using both the Statements together, but cannot be answered by using either Statement alone.  
  4. Choose this option if the Question cannot be answered even by using both Statements together.

Answer (Detailed Solution Below)

Option 3 : Choose this option if the Question can be answered by using both the Statements together, but cannot be answered by using either Statement alone.  
Free
UPSC CDS 01/2025 General Knowledge Full Mock Test
8.1 K Users
120 Questions 100 Marks 120 Mins

Detailed Solution

Download Solution PDF

Calculation:

Statement I: (x + y)4 = 256

(x + y)4 = 164

(x + y) = ± 4

So, no unique values of x, and y are possible from this statement alone.

Statement II: (x + y)3 < 16

No unique values of x, and y are possible from this statement alone.

Let's combine both statements

Let x = 4

(4)3 < 16 

64 < 16 which is wrong

If x = -4

-64 < 16 which is correct.

So, (x + y) = - 4 

∴ Optipon 3 is correct.

Latest CDS Updates

Last updated on Jul 7, 2025

-> The UPSC CDS Exam Date 2025 has been released which will be conducted on 14th September 2025.

-> Candidates can now edit and submit theirt application form again from 7th to 9th July 2025.

-> The selection process includes Written Examination, SSB Interview, Document Verification, and Medical Examination.  

-> Attempt UPSC CDS Free Mock Test to boost your score.

-> Refer to the CDS Previous Year Papers to enhance your preparation. 

More Data Sufficiency Questions

Get Free Access Now
Hot Links: teen patti 3a teen patti star login online teen patti real money