How Old is Everyone?

My friend Alice reminds me of me: she has two sons and she is never straight with her age. Or, maybe, she just isn’t very good with numbers.

Once I visited her family for dinner and asked her point blank, “How old are you?” Here is the rest of the conversation:

Alice: I am two times older than my younger son was 5 years ago.
Bob: My mom is 12 times older than my older brother.
Carl: My younger brother always multiplies every number he mentions by 24.
Bob: My older brother is 30 years older than me.
Carl: My mom is 8 times older than me.
Alice: My older son always multiplies every number he mentions by 2.

How old is everyone?



  1. Games Developer:

    Turns out Alice always divides every number she mentions by 2. It means that Carl multiplies his numbers by 4, and Bob multiplies his numbers by 6.

    A = 4 * (B – 10)
    A = 2 * C
    C = B + 5

    So B = 25; C = 30; A = 60;

    No wonder, Alice reminds you of you Tanya! But you are very good with numbers! 😉

  2. CyberK:

    Makes sense I suppose, now that I see the solution, but I gotta say it wasn’t obvious to me that “isn’t very good with numbers” necessarily meant “being a linear factor off” nor that she was consistently making the same error.

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