Posted 14 Mar 2013 Two consecutive numbers are given to A and B. when A is asked ‘do you know B’s number?’ A denies. when B is asked whether he knows A’s no., B also denies. at the very moment, A replies that he knows B’s number. what may be B’s number? 0 Share this post Link to post Share on other sites

0 Posted 14 Mar 2013 Assuming that the OP implied that the two consecutive positive integers were given to A and B, then B has 3 and A has 2. This puzzle cannot be solved unless a bounded range of numbers is given. The OP simply states that the numbers are consecutive. If the numbers are drawn from an unbounded range then neither A nor B can ever deduce the other's number. 1 Share this post Link to post Share on other sites

0 Posted 15 Mar 2013 Since A & B are given the consecutive numbers therefore the numbers must be 2 & 3, considering that zero has no value so not counted as number, and no negative or fractional quantity is chosen. Explanation is: when first time asked 'A' could not answer because he had two and 'B' could have any of the number 1 or 3; Then when B is asked he could not reply because he had number 3, and A could have any number 2 or 4. But B's answer ascertained A that B did not have 1, otherwise he could have definitely known that A has numbere 2 (zero is not considered as number). Therefore obviously A comes to know that B has Number 3. 0 Share this post Link to post Share on other sites

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Two consecutive numbers are given to A and B. when A is asked ‘do you know B’s number?’ A denies. when B is asked whether he knows A’s no., B also denies. at the very moment, A replies that he knows B’s number. what may be B’s number?

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