Question

The Unexpected Test.† In a certain mathematics class Professor B, who always tells the truth and is never mistaken, explains the marking scheme for the course to the students.

“This course meets once each week. There will be only one test, which will be written in class in one of the twelve weeks of the next term. However you will not know which week it is until the class in which the test is given.”

Is there any way to determine in which week the test is given? Explain why or why not. If there is, in which week will the test be written? [10]

Answer 1

Students expect that the test will be in the class in the twelfth week if he did not conduct the test in the first eleven weeks. In that case it will not be an unexpected test. So he can not give the test in the twelfth week.

So no test in 12 the week

So they expect that ... at the most he has to conduct the test on the eleventh week. So conducting the test on the eleventh week also will not be an unexpected test.

so no test in 11 th week.

proceeding like this

whenever he conducts the test It is not an unexpected test..