- Bookworm
-
A bookworm eats from the first page of an encyclopedia to the last
page. The bookworm eats in a straight line. The encyclopedia consists
of ten 1000-page volumes and is sitting on a bookshelf in the usual
order. Not counting covers, title pages, etc., how many pages does the
bookworm eat through?
Answer
- Which Box Contains the Gold?
-
Two boxes are labeled "A" and "B". A sign on box A says "The sign
on box B is true and the gold is in box A". A sign on box B says
"The sign on box A is false and the gold is in box A". Assuming there
is gold in one of the boxes, which box contains the gold?
Answer
- Camel Race
-
An Arab sheikh tells his two sons to race their camels to a distant
city to see who will inherit his fortune. The one whose camel is
slower will win. The brothers, after wandering aimlessly for days, ask
a wise man for advise. After hearing the advice they jump on the
camels and race as fast as they can to the city. What does the wise
man say?
Answer
- Centrifuge
-
You are a biochemist, working with a 12-slot centrifuge.
This is a machine that has 12 equally spaced slots around a central
axis, in which you can place tubes containing chemical samples you
want separated.
When the machine is turned on, the samples whirl around the central
axis and the denser substances are forced to the bottom of the tubes.
To ensure that the samples are well separated,
they must be distributed in the
12 slots such that the centrifuge is balanced evenly.
For example, if you
wanted to centrifuge 4 samples,
you could place them in slots 12, 3, 6 and 9
(assuming the slots are numbered from 1 to 12 like a clock).
Problem: Can you use the centrifuge to separate 5 samples?
Answer
- Elimination
-
97 baseball teams participate in an annual state tournament.
The way the champion is chosen for this tournament is by the same old
elimination schedule. That is, the 97 teams are to be divided into
pairs, and the two teams of each pair play against each other.
After a team is eliminated from each pair, the winners would
be again divided into pairs, etc. How many games must be played
to determine a champion?
Answer
- Flowers
-
How many flowers do I have if all of them are roses except two, all of
them are tulips except two, and all of them are daisies except two?
Answer
- Locks and Boxes
-
You want to send a valuable object to a friend. You have a box which
is more than large enough to contain the object. You have several
locks with keys.
The box has a locking ring which is more than large enough
to have a lock attached. But your friend does not have the key to any
lock that you have. How do you do it? Note that you cannot send a key
in an unlocked box, since it might be copied.
Answer
- Mixing Tea and Coffee
-
Start with a half cup of tea and a half cup of coffee.
Take one tablespoon of the tea and mix it in with the coffee.
Take one tablespoon of this mixture and mix it back in with the tea.
Which of the two cups contains more of its original contents?
Answer
I've had a few emails disagreeing with the answer. I think it's correct,
and here's why.
