Q.9 Given below are two statements and four conclusions drawn based on the
statements.
Statement 1: Some soaps are clean.
Statement 2: All clean objects are wet.
Conclusion I: Some clean objects are soaps.
Conclusion II: No clean object is a soap.
Conclusion III: Some wet objects are soaps.
Conclusion IV: All wet objects are soaps.
Which one of the following options can be logically inferred?
(A) Only conclusion I is correct
(B) Either conclusion I or conclusion II is correct
(C) Either conclusion III or conclusion IV is correct
(D) Only conclusion I and conclusion III are correct
Syllogism Reasoning Question: Some Soaps Are Clean, All Clean Objects Are Wet
The correct answer is option (D) Only conclusion I and conclusion III are correct. This syllogism follows standard logical rules where “some A are B” combined with “all B are C” guarantees certain conclusions but not others.
Venn Diagram Analysis
Draw two overlapping circles: one for soaps (S), one for clean objects (C), and one for wet objects (W). Some soaps overlap with clean objects, and all clean objects fall entirely within wet objects. This creates a region where some soaps must be both clean and wet.
Conclusion Breakdown
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I: Some clean objects are soaps – True, as the “some soaps are clean” directly converts to this via overlap.
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II: No clean object is a soap – False, directly contradicts the overlap from statement 1.
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III: Some wet objects are soaps – True, since those clean soaps (from I) must also be wet per statement 2.
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IV: All wet objects are soaps – False, as wet objects extend beyond clean ones with no soap relation.
Option Evaluation
| Option | Claim | Valid? | Reason |
|---|---|---|---|
| (A) | Only I correct | No | III also follows logically |
| (B) | Either I or II | No | Both cannot hold; II contradicts I |
| (C) | Either III or IV | No | Both cannot hold; IV overreaches |
| (D) | I and III correct | Yes | Matches definite inferences from premises |
In competitive exams like GATE Civil, CSIR NET Life Sciences, and others, syllogism reasoning questions test deductive logic through statements like “some soaps are clean all clean objects are wet.” These appear frequently in general aptitude sections, requiring Venn diagram mastery to identify valid conclusions quickly.
Why This Syllogism Matters for CSIR NET
CSIR NET aspirants encounter such syllogism some soaps are clean all clean objects are wet patterns to evaluate if conclusions like “some clean objects are soaps” logically follow. The structure—”Some A are B; All B are C”—always yields “Some A are C” and extends to “Some C are A,” but never universal claims.
Step-by-Step Solving Technique
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Convert statements: Soaps partially overlap cleans; cleans fully subset wets.
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Test each conclusion against minimum Venn overlap.
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Eliminate options with invalid pairs (e.g., no “either-or” here).
Pro Tip: For “some + all” cases, reverse direction yields valid “some” conclusions; avoid “all” or “no” overextensions.
