Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Markjay]

(Found on the net, no copyright claimed)


The teacher tells her students that they should expect an exam some time during the next week. But she does not say when. The exam is to be unexpected.

But will it be unexpected?

Can the teacher give the exam on Friday? No, for if she gives it on Friday, then on Friday morning her students, knowing that they hadn't had the exam earlier in the week, will expect it.

What about Thursday? Well, as her students know that the exam cannot be on Friday, if she leaves it till Thursday, the exam will again be expected. So Thursday is out, too.

What about Wednesday? That, again, is ruled out. Her students know the exam cannot be on either Thursday or Friday, so if the teacher leaves it until Wednesday, the exam will again be expected.

But then Tuesday and Monday are also out, and for the same reason.

In short, the teacher cannot give an unexpected examination.

Yet, of course, she can. Can't she?

[Entwood]

Old chestnut .....  the flaw in this "logic" is in the question ... it works backwards from Friday to Monday and each step is based on the previous one. In reality life flows in the other direction .. from Monday to Friday so the arguments don't stand except for the first (which should be the last) .. if the exam has NOT occured by school closing on Thursday then it must occur on Friday, at this point it is no longer "unexpected"   but up until that point  it would be.

[paul.c]

 did you pass the exam or not .?  :-?

[Danny]

"expect an exam some time next week"

therefore its expected!

[TheBoy]

don't tell them....