i've a better idea, let's put it another way...based on the 10
doors problem
i think of a number 1 to 10, you are supposed to guess that
number
10 numbers are really hard to choose one from, say you choose
1.
now i say: 2,3,4,5,6,8,9,10 are NOT the correct answers
can you see something now? a very obvious hint that the 'gap' is
probably the correct answer.
now all is left is 1 and 7. would you like to change your ans to 7?
or insist on 1?
by common sense, i'm sure the choice to change or not is more or
less decided.
can you still say the odds is still 50:50?
[in fact the odds are 1:9]
the reason why we dun see this in the 3 doors problem is becos the
number of doors is too few (it's the minimum for this problem to
work). ppl usually cannot detect the small difference of
probability 2/3 and 1/2 through their intuition or common sense