Question 946167
Phil, Steve, and Esther are aged 19 – 22, and none of them is the same age.
Phil's age is an even number, and Steve and Esther have consecutive ages.
Steve's age is an odd number, and he is older than Phil. Who is the oldest? 
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Steve's age is an odd number...
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So Steve is either 19 or 21
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and he (Steve) is older than Phil.
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So Steve is 21, for if he were 19, Phil would be 18 or younger, not allowed.
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and he (Steve) is older than Phil.
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So Phil is either 19 or 20.
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Phil's age is an even number,
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So Phil is 20.
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Steve and Esther have consecutive ages.
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Since Steve is 21, Esther is either 20 or 22
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none of them is the same age
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Since Phil is 20, Esther can't be, so she is 22, and
therefore she is the oldest.

Edwin</pre>