I bypass the minor "tricky" statements - no problem to identify the doors (and no problemas with the knobs). I try to see he questions as fair as logical.
So, it seems a matter of determine slices of time (8 unknown and 2 known - 10 slices). And to measure time we need a reference. So we can...
A few years ago a tryed to solve this problem. A got some reasonable solutions and one very good solution (I think the central question is to obtain a accurate way to masure time) but I don´t know if it´s the best one. This problem is from sigmasociety.com:
An Arab man and an Israeli woman...
Everyday a man comes from work and get out the train, at station, at 5 PM. At the same time, everyday, his wife, driving a car, takes him and they go home.
One day, the man leaves his work early and get on the sation at 4 PM. So, he decides to go home walking. On the way home, he meets his...
Monty Hall Problem: it´s easy to understand it with 10 doors. There is a 1/10 possibilty of picking the correct door and 9/10 possibility of picking the wrong door. You make your choice. And after 8 of the empty doors has been revealed, you choice still 1/10 possibilty of picking the correct...
Two pieces, side by side, are falling down, into vacuum, by the only attraction of a planet gravity. One is 1.000 Tons weight and the other piece is 0,001 Tons weight.
Wich one is going to hit the planet´s ground first?
First, try to use your own sense.
Take a twine (rope) and put it around a ball, or an orange (sphere).
Now you have the circumference (perimeter) of that sphere.
Take this twine and add 1m more (one more meter - it can be any unit of liner measure).
Put this one meter longer twine around...