This page covers RRB Group D Data Sufficiency — Reasoning with complete concept notes, 4 graded practice MCQs, key points and exam-specific tips. Free to study.
Core ConceptRead this first — the foundation of the topic
Data Sufficiency is a unique question type where you don't solve the problem completely. Instead, you determine whether the given information is enough to answer the question. Think of it as being a detective - you need to check if the clues are sufficient to solve the case. In SSC CGL, data sufficiency questions typically provide a question followed by two statements (I and II). Your job is to decide which combination of statements can answer the question. The standard answer choices are:
A) Statement I alone is sufficient B) Statement II alone is sufficient
C) Both statements together are sufficient D) Neither statement is sufficient
E) Each statement alone is sufficient Key Rules: Never assume information not given. Don't make calculations unless necessary - just check if calculation is possible. Focus on 'Can I solve?' not 'What is the answer?'. Remember that 'sufficient' means you can find a unique answer, not multiple possibilities.
Exam PatternsWhat examiners ask — read before attempting PYQs
SSC CGL asks 2-3 data sufficiency questions per paper. Common topics include ages, profit-loss, time-work, geometry, and number problems. Questions often test logical thinking more than mathematical computation.
Powerful Shortcut: Use the SCAN method - S(can I solve with Statement I alone?), C(an I solve with Statement II alone?), A(re both needed together?), N(ot sufficient even together?). This systematic approach prevents confusion and saves time.
Worked ExampleSolve this step-by-step before moving on
1
Step 1
Check Statement I alone
Statement I gives us: Ram = Shyam + 5
This has two unknowns but only one equation. We cannot find Ram's exact age.
Statement I alone: NOT SUFFICIENT
2
Step 2
Check Statement II alone
Statement II gives us: Ram + 10 = 2 × (Shyam's current age)
Again, two unknowns, one equation. Cannot find exact ages.
Statement II alone: NOT SUFFICIENT
3
Step 3
Check both statements together
From I: Ram = Shyam + 5, so Shyam = Ram - 5
From II: Ram + 10 = 2 × Shyam
Substituting: Ram + 10 = 2(Ram - 5)
Ram + 10 = 2Ram - 10
20 = Ram
Both statements together give us Ram's age as 20 years.
Answer: C) Both statements together are sufficient
Exam TrapsCommon mistakes students make — avoid these
Students often try to solve the complete problem instead of just checking sufficiency. This wastes time and can lead to wrong conclusions. Another trap is assuming obvious information that isn't stated - stick strictly to what's given.
Remember: In data sufficiency, your goal is to be a judge, not a calculator.
Judge whether the evidence is enough to reach a verdict.
Key Points to Remember
Data sufficiency tests whether given information is enough to answer the question, not the actual answer
Standard format includes a question followed by two statements I and II
Five answer choices cover all combinations of statement sufficiency
Never assume information that is not explicitly provided in the statements
Focus on 'Can I solve?' rather than 'What is the solution?'
Use SCAN method: check Statement I alone, Statement II alone, both together, neither sufficient
Sufficient means you can find one unique answer, not multiple possibilities
Most common topics are ages, profit-loss, time-work, and basic geometry problems
Exam-Specific Tips
SSC CGL includes 2-3 data sufficiency questions per reasoning section
Standard answer choices are always A, B, C, D, E representing different statement combinations
Data sufficiency questions carry same marks as other logical reasoning questions
Age-related problems appear in 40% of data sufficiency questions in SSC exams
Time allocation should be maximum 2 minutes per data sufficiency question
Geometry-based data sufficiency questions often involve finding area or perimeter
Number theory problems frequently test concepts of even, odd, and prime numbers
Practice MCQs
Data Sufficiency — Reasoning — Practice Questions
4graded MCQs · easy to hard · full solution & trap analysis
Study the following statements and determine whether the data provided is sufficient to answer the question.
Question: Is Rajesh taller than Priya?
Statement I: Rajesh is taller than Amit, and Amit is taller than Priya.
Statement II: Priya is shorter than Rajesh.
Which of the following is correct?
(A) Statement I alone is sufficient, but Statement II alone is not sufficient.
(B) Statement II alone is sufficient, but Statement I alone is not sufficient.
(C) Both statements together are sufficient, but neither alone is sufficient.
(D) Either statement alone is sufficient.
Practice 2medium
Is Ramesh older than Priya?
Statement I: Ramesh is 5 years older than Suresh, and Suresh is 3 years older than Priya.
Statement II: The sum of Ramesh's and Priya's ages is 54 years, and their age difference is 8 years.
Practice 3medium
Five friends—Anil, Bina, Chetan, Diya, and Esha—sit in a row facing North. Statement I: Anil sits immediately to the left of Bina. Statement II: Chetan sits at one of the ends. Statement III: Diya and Esha are not adjacent to each other. Is it possible to determine the exact seating arrangement of all five friends using these statements?
Practice 4hard
Five friends—Arun, Bhavna, Chitra, Deepak, and Esha—sit in a row facing North. The following conditions apply:
1. Arun sits immediately to the left of Bhavna.
2. Chitra does not sit at either end.
3. Deepak sits to the right of Esha.
4. The person second from the left is not Deepak.
5. Esha is not adjacent to Bhavna.
Statement I: Chitra sits in the middle position.
Statement II: Arun sits to the left of Esha.
Which statement(s) alone is/are sufficient to determine the complete seating arrangement?
A) Statement I alone is sufficient, but Statement II alone is not sufficient.
B) Statement II alone is sufficient, but Statement I alone is not sufficient.
C) Both statements together are sufficient, but neither alone is sufficient.
D) Neither statement alone nor both together are sufficient.
60-Second Revision — Data Sufficiency — Reasoning
Remember: Judge sufficiency, don't calculate the actual answer unless necessary
Formula: Use SCAN method to systematically check each statement combination
Trap: Never assume information not explicitly stated in the problem
Strategy: If one statement alone works, don't waste time checking combinations
Focus: Look for unique answer possibility, not multiple solutions
Time tip: Spend maximum 2 minutes per question using elimination method