More Questions from Statement and Conclusion

In this statement and conclusion question involving animals, two statements describe relationships among crows, jackals, and foxes. You must treat the statements as true and decide which of the conclusions I and II logically follow. Statement I: Some crows are jackals. Statement II: No fox is a crow. Conclusion I: Some jackals are foxes. Conclusion II: Some jackals are not foxes.

Verbal Reasoning Statement and Conclusion Difficulty: Medium
Choose an option
  • A
    Conclusion I follows
  • B
    Conclusion II follows
  • C
    Either I or II follows
  • D
    Both I and II follows
  • E
    Neither I nor II follows

Answer

Correct Answer: Conclusion II follows

Explanation

Introduction / Context: This question deals with logical relations among three sets that correspond to animals: crows, jackals, and foxes. You must interpret the sets abstractly and ignore real world biology. The statements describe overlap between crows and jackals and a complete separation between crows and foxes. You then judge whether the conclusions about jackals and foxes follow from this information.

Given Data / Assumptions: - Statement I: Some crows are jackals, meaning the intersection between the sets of crows and jackals is non empty. - Statement II: No fox is a crow, meaning the sets foxes and crows are completely disjoint. - Conclusion I: Some jackals are foxes, which asserts that the jackal set and fox set have a non empty intersection. - Conclusion II: Some jackals are not foxes, which asserts that at least one jackal lies outside the fox set.

Concept / Approach: Use set notation: let C be the set of crows, J the set of jackals, and F the set of foxes. From Statement I, C ∩ J is non empty. From Statement II, F ∩ C is empty. We are asked about the relation between J and F. Notice that there is at least one element that is both a crow and a jackal, and that no element of C can be in F. This will help us decide whether there must exist jackals that are not foxes.

Step-by-Step Solution: Step 1: Because some crows are jackals, there exists an element x such that x ∈ C and x ∈ J. Step 2: Because no fox is a crow, no element of C can also belong to F. Symbolically, C ∩ F is empty. Step 3: Since x is in C, x cannot be in F. Therefore, x is a jackal that is not a fox. Step 4: This directly proves that at least one jackal is not a fox, which means Conclusion II must be true. Step 5: Now check Conclusion I, which says some jackals are foxes. We have no information that connects J directly to F other than the indirect connection through C, and that connection only tells us that some jackals are crows, not that any jackals are foxes. Step 6: It is possible to draw a Venn diagram where J and F have no overlap at all, while still satisfying both statements. In that case, Conclusion I would be false. Step 7: Therefore, Conclusion I does not logically follow, while Conclusion II is necessarily true.

Verification / Alternative check: Draw C and J so that they overlap in some region, representing crows that are jackals. Then draw F as a separate set that does not touch C at all, as required by Statement II. Because the overlapping region C ∩ J is prohibited from lying in F, there is at least one jackal in that overlap which cannot be a fox. Thus the existence of a jackal that is not a fox is guaranteed in every diagram, confirming Conclusion II. At the same time, you can place F completely away from J, showing that some jackals are foxes is not forced by the statements.

Why Other Options Are Wrong: Option A picks Conclusion I, which is not supported. Option C suggests that exactly one of I or II follows but leaves ambiguity; however, the question requires a specific choice. Option D claims both conclusions follow, which cannot be because one conclusion is optional while the other is necessary. Option E says neither follows, which is wrong because Conclusion II definitely follows from the given information.

Common Pitfalls: Some test takers think that if some crows are jackals and no fox is a crow, they lack enough information and might conclude nothing follows. In fact, the overlap between crows and jackals combined with the separation of crows and foxes gives a guaranteed example of a jackal that is not a fox. Another pitfall is to assume that some jackals are foxes based on loose real world associations, which is not allowed in pure logic problems.

Final Answer: The correct option is Conclusion II follows, because there must exist at least one jackal that is not a fox, while there is no logical requirement that any jackal has to be a fox.

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