Personal Comment: Easy. Short. Silly.

Bob's Age Enigma

What we know: Jim is 36 years old. Mary is 27.5(according to a previous enigma). Bob is single and he wants to post himself in the paper but he forgot how old he is. Jim was twice as old as Bob was when Jim was as old as Bob is now. But Jim is gay.

Enigma: How old was Bob a year ago?

Solution: This solution was sent in by Stephan Ahonen. I liked it so much, i used it for the solution: Bob was 23. I had to think really hard about it before I reread the problem and hit myself on the head several times after realizing that it says Jim's age right in the problem. I also stumbled a little bit over the wording.

Anyway, I did it by drawing a diagram:

36-Jim(now)

x-Jim(then) and Bob(now)

1/2x-Bob(then)

The number "3" popped out of my subconcious mind. I will never know where I got that idea. So I divided 36 by 3 and got 12 for the lowest level and 24 for the middle level:

36-J(now)

24-J(then) and B(now)

12-B(then)

This is asking for Bob's age a year ago, subtract 1 from the middle space on the diagram and presto!!

The difficulty is "x" because:

a)it depends on how good you are at interpreting wording and

b)because many thousands of people will miss the "Jim is 36" thing and say that "Bob is 1/3 of the cosine of the coefficient of the prosignon parameter of the melting point of turkey years old."

See who got this right

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