If Ram knows that y is an integer greater than 2 and less than 7 and Hari…
2012
If Ram knows that y is an integer greater than 2 and less than 7 and Hari knows that y is an integer greater than 5 and less than 10, then they may correctly conclude that
Answer: A. y can be exactly determined — Concept: When several conditions must hold simultaneously, the admissible values are the intersection of the sets defined by those conditions. For strict…
- A.
y can be exactly determined
- B.
y may be either of two values
- C.
y may be any of three values
- D.
there is no value of y satisfying these conditions .
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Show answer & explanation
Correct answer: A
Concept: When several conditions must hold simultaneously, the admissible values are the intersection of the sets defined by those conditions.
For strict integer bounds a < y < b, only the integers strictly between a and b are included.
Application
Ram’s information gives the integer set {3, 4, 5, 6} because 2 < y < 7.
Hari’s information gives the integer set {6, 7, 8, 9} because 5 < y < 10.
Their common set is {3, 4, 5, 6} ∩ {6, 7, 8, 9} = {6}.
Cross-check
Equivalently, the stronger lower bound is 5 and the stronger upper bound is 7. The only integer strictly between them is 6.
Result
Therefore, y is exactly determined as 6.