A professor tells his class that he will give them a surprise examination sometime next week.

For our purposes, an examination is considered a "surprise" if on that day, the class is not 100% sure that they will get an examination. (If they only suspect it, the examination can still be a surprise.)

Having given the class this warning, is it still possible for the professor to give them a surprise examination next week? (Assume that he will not give them an exam if it will not be a surprise.)

we as can eliminate the days one by one by saying this, but the only one which will be true could be that if it came to the end of thursday and the teacher hasn't given them an exam then they will expect one on friday, but when you eliminate thursday then wednesday as possible exam days you can re open friday and thursday and so on as the class will have discounted these as days and thus won't be expecting them

Posted by mullen on 2003-06-21 03:28:59