A puzzle… after a long time…
Getting bored in the loooooong flight back. Suddenly remembered an email exchange I had with my friend Mita this week. It was actually a puzzle. In all honesty, I had heard a puzzle somewhat like that, so I was able to get it. Figured I will post it here.
The challenging part of the puzzle is its incredible simplicity. There are no catches in the puzzle. But the simplicity is bound to confuse readers. So here it goes…
“John called Mary. Mary called Tom. John is married but Tom is not”.
From the above, can you say whether the following statement
“A married person called an unmarried person” is
(a) Definitely True
(b) Definitely False
(c) Insufficient information to say whether True or False.
Send me personal message instead of putting in Comments and I will respond.
Devashish has been the first one to get the answer right
Pradeep got it too
As did Madhusudhan
And Rupa
And Linda
This puzzle doesn’t seem to meet the standard required to be a Rajib Roy puzzle.
Manish, nobody has ever accused me of having standards đŸ™‚
Jasmine and Santosh got it too.
And Sanjay
Add Ramesh
ANSWER: The simplicity of the problem is pretty confounding.
Many came up with “c”. which at first glance might make sense – how do we know whether Mary is married or not? to be able to definitely say.
In reality though, it does not matter at all… If Mary is married then because she talked to Tom, the statement is true. If she is unmarried then since John talked to her, the statement is again true…
This can be generalized to any length of a chain of binary nodes as long as the first node and last node are opposite. There has to be at least one node that switches the polarity…