Time-sequence / date intersection: Adi remembers Ana’s birthday is after 20th September but before 23rd. Father remembers it is after 21st and before 24th September. Determine Ana’s correct date of birth.
Verbal Reasoning
Time Sequence
Difficulty: Easy
Choose an option
-
A21st September
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B22nd September
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C23rd September
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D24th September
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ENone of these
Answer
Correct Answer: 22nd September
Explanation
Introduction / Context:Two interval clues must be intersected to find a unique date. “After” and “before” are strict inequalities (exclude endpoints).
Given Data / Assumptions:
- Adi: 20 < date < 23 ⇒ {21, 22}.
- Father: 21 < date < 24 ⇒ {22, 23}.
Concept / Approach:Take the intersection of the two candidate sets to find the only date satisfying both memories.
Step-by-Step Solution:
From Adi: {21, 22}.From Father: {22, 23}.Intersection: {22} ⇒ 22nd September.Verification / Alternative check:22 is indeed after 20 and before 23, and after 21 and before 24.
Why Other Options Are Wrong:21 contradicts Father’s “after 21”; 23 contradicts Adi’s “before 23”; 24 is out of both ranges.
Common Pitfalls:Treating “after/before” as inclusive bounds.
Final Answer:22nd September