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    A professor thinks of two consecutive numbers between 1 and 10.
    'A' knows the 1st number and 'B' knows the second number

    A: I do not know your number.
    B: Neither do I know your number.
    A: Now I know.

    There are four solution for this.What are they ??
    -----------
    My answer an reasoning
    A = 2 B=3
    A=9 B=8
    (i.e: two solutions - I cannot find 4?)
    If A has 2 then B has either 1 or 3 BUT if B had 1 then he would know A's number as they are consecutive: hence A=2, B=3
    The same logic applies for 9,8

    How are there for solutions and what are they?
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    The answer is 1. The answer in maths problems is always 1. Always.
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    (Original post by jsmith6131)
    A professor thinks of two consecutive numbers between 1 and 10.
    'A' knows the 1st number and 'B' knows the second number

    A: I do not know your number.
    B: Neither do I know your number.
    A: Now I know.

    There are four solution for this.What are they ??
    -----------
    My answer an reasoning
    A = 2 B=3
    A=9 B=8
    (i.e: two solutions - I cannot find 4?)
    If A has 2 then B has either 1 or 3 BUT if B had 1 then he would know A's number as they are consecutive: hence A=2, B=3
    The same logic applies for 9,8

    How are there for solutions and what are they?


    A:3, B must have 2 or 4. If 2, B would have knew the answer already, because A said he doesn't know so it can't be 1? A knows B doesn't know so he knows it isn't 2. So it's 3 and 4.

    okay one more to go.

    Edit: Reading over my answer, I don't think I have been very clear in my reasoning lol.
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    (Original post by amineamine2)
    okay one more to go.
    +rep.

    And apply the same argument to A=8,B=7
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    (Original post by ghostwalker)
    +rep.

    And apply the same argument to A=8,B=7
    Thank you. I had just gone down a reputation level so quite pleased over your rep (as I'm now back to two green boxes)
 
 
 
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