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  Reasoning

Not Enough Time
 
Q Larry insists that he does not have enough time to go to school more than 17 days a year. He comes to this conclusion based on the following list that he put together.

Activity Number of days
per year
Sleep (8 hours a day) 122
Meals (2 hours a day) 31
Weekends 104
Summer vacation 60
Recreation (2 hours a day) 31
Total 348

Inspired by the list, Larry claims he has only 17 days left in the year for school. What's wrong with his thinking?


 
A Larry's categories overlap. For example, he has counted 60 days for vacation, during which time he will both eat and sleep, activities that he has already counted separately. The 60 vacation days also include weekends, another category that he has already counted separately. He should not count the same periods of time more than once.

Inspired by a puzzle inMathematical Puzzlesby Martin Gardner. New York: Thomas Y. Crowell Company, 1961.