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Prime Suspects

Probability puzzles require you to weigh all the possibilities and pick the most likely outcome.


Puzzle ID:#29151
Fun:*** (2.58)
Difficulty:** (1.95)
Submitted By:Jimbo*au******
Corrected By:brainster




Two hundred people in an auditorium are asked to think of a single digit number from 1 to 9 inclusive and write it down. All those who wrote down a prime number are now asked to leave. Ninety people remain behind in the hall. How many of these are expected to have written down an odd number?

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