This page covers SSC MTS Data Sufficiency β Reasoning with complete concept notes, 16 graded practice MCQs, key points and exam-specific tips. Free to study.
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.
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Exam Patterns
What examiners ask β 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.
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Worked Example
Solve 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 Γ (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 Γ 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
Common Mistake: 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.
Test Data Sufficiency β Reasoning under exam conditions
Statements:
I. All teachers are educated.
II. Some educated people are doctors.
Question: Can we conclude that some teachers are doctors?
A) Yes, the conclusion definitely follows
B) No, the conclusion does not follow
C) Yes, the conclusion probably follows
D) Cannot be determined
Practice 2easy
Statements:
I. No politician is honest.
II. Some honest people are rich.
Question: Can we conclude that some rich people are not politicians?
A) Yes, definitely
B) No, does not follow
C) Probably yes
D) Cannot be determined
Practice 3easy
Statements:
I. All fruits are sweet.
II. All sweet things are healthy.
III. Some apples are fruits.
Question: Can we conclude that some apples are healthy?
A) Yes, definitely
B) No, does not follow
C) Cannot be determined
D) Probably yes
Practice 4easy
Statements:
I. All engineers are problem-solvers.
II. No problem-solver is lazy.
Question: Can we conclude that no engineer is lazy?
A) Yes, definitely
B) No, does not follow
C) Cannot be determined
D) Probably yes
Practice 5easy
Statements:
I. All doctors are professionals.
II. Some professionals are wealthy.
III. All wealthy people are educated.
Question: Can we conclude that some doctors are educated?
A) Yes, definitely
B) No, does not follow
C) Cannot be determined
D) Probably yes
Practice 6easy
Statements:
I. Some students are athletes.
II. All athletes are disciplined.
III. Some disciplined people are not teachers.
Question: Can we conclude that some students are not teachers?
A) Yes, definitely
B) No, does not follow
C) Cannot be determined
D) Probably yes
Practice 7medium
Statements:
I. All managers are leaders.
II. Some leaders are innovators.
III. No innovators are followers.
Question: Can we conclude that 'Some managers are not followers'?
A) Yes, the conclusion definitely follows
B) No, the conclusion does not follow
C) The data is insufficient to draw any conclusion
D) Yes, but only if we assume all innovators are leaders
Practice 8medium
Statements:
I. All doctors are professionals.
II. Some professionals are not teachers.
III. All teachers are educated.
Question: Can we conclude that 'Some doctors are not educated'?
A) Yes, definitely
B) No, it does not follow
C) Only if all professionals are educated
D) Only if some doctors are teachers
Practice 9medium
Statements:
I. Some politicians are honest.
II. All honest people are trustworthy.
III. No trustworthy person is corrupt.
Question: Can we conclude that 'Some politicians are not corrupt'?
A) Yes, the conclusion definitely follows
B) No, the conclusion does not follow
C) Yes, but only if all politicians are honest
D) Cannot be determined from the given information
Practice 10medium
Statements:
I. All successful entrepreneurs are risk-takers.
II. No risk-taker is fearful.
III. Some ambitious people are fearful.
Question: Can we conclude that 'Some ambitious people are not successful entrepreneurs'?
A) Yes, the conclusion definitely follows
B) No, the conclusion does not follow
C) Yes, but only if all ambitious people are risk-takers
D) Yes, but only if some risk-takers are ambitious
Practice 11hard
A person travels from City X to City Y. Statement I: The person travels 40 km north, then 30 km east. Statement II: The person's final displacement from City X is 50 km. Which statement(s) is/are necessary to determine the straight-line distance between City X and City Y?
Practice 12hard
A person's age is being determined. Statement I: The person's age is 5 years more than twice the age of their younger sibling. Statement II: The sum of their age and their sibling's age is 35 years. Can we determine the person's exact age?
Practice 13hard
In a group of students, some study Mathematics, some study Physics, and some study both. Statement I: 60% of students study Mathematics. Statement II: 40% of students study Physics. Can we determine what percentage of students study both subjects?
Practice 14hard
A shopkeeper sells three types of items: X, Y, and Z. Statement I: The ratio of items sold is X:Y:Z = 2:3:5. Statement II: The total number of items sold is 100. Can we determine the exact number of item X sold?
Practice 15hard
A company has employees in three departments: Sales, Marketing, and Operations. Statement I: The number of employees in Sales is 20% more than in Marketing. Statement II: The number of employees in Operations is 15% less than in Marketing. Is Statement I alone sufficient to determine the exact number of employees in Sales?
Practice 16hard
Five peopleβA, B, C, D, Eβsit in a row. Statement I: A sits immediately to the left of C. Statement II: B sits at one end, and D sits immediately to the right of B. Is Statement I alone sufficient to determine the exact seating arrangement?
60-Second Revision β Data Sufficiency β 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