Can you connect these nine dots with just 4 straight
lines?
Answer
Men
with Hats
There are 4 men each wearing a either a black or a white hat. They
are standing in rising water, cannot move and can only look forward.
Between A and B is a brick wall which they cannot see through.
They know that between them are 4 hats of which 2 are black and 2
are white, but they do not know which colour they are wearing.
In order to stop the level of the water rising and drowning, one
of them must call out correctly which colour hat he is wearing. They
are not allowed to talk to each other and have 10 minutes to fathom
it out.
Which one of them calls out, and how does he work out which colour
he is wearing?
Answer
The
Lights on the Second Floor
You have just walked into a dark two-storey house. There are three
light switches on the first floor A, B and C. Only one of the switches
works, and it turns on the light on the second floor.
You cannot see the second floor light from the first floor and there
are no windows in the building, but you do have a flashlight.
You can only make one trip up the stairs, and you can only flip one
switch at a time. How do you determine which of the three switches
turns on the light on the second floor ?
Twin
Brothers
You are travelling down a road to a village. You reach a fork in
the road and find a pair of identical twin brothers standing there.
One of the brothers always tells the truth and the other always lies.
If you are allowed to ask only one question to one of the
brothers to find which is the correct road to the village, what is
your question ?
Bottle
of Wine
A bottle of wine cost £10. The wine was worth £9 more
than the bottle.
How much was the bottle worth?
Answer
The
Bear
There is a house with four walls. Each wall faces south. There is
a window in each wall.
A bear walks by one of the windows. What colour is
the bear?
Answer
The
Ladder
A boat has a ladder that has six rungs, each rung is one foot apart.
The bottom rung is one foot from the water. The tide rises at 12 inches
every 15 minutes. High tide peaks in one hour.
When the tide is at its highest, how many rungs are under water?
Answer
You have two buckets - one holds exactly 5 gallons and the other
3 gallons
How can you measure out 4 gallons of water into the 5 gallon bucket
?
(Assume that you have an unlimited supply of water and that there
are no measurement markings of any kind on the buckets.)
Answer
The
Third Word
Think of words ending in 'gry'.
Angry and hungry are two of them.
There are only three words in the English language.
What is the third word?
The word is something that everyone uses every day.
If you have read this very carefully,
I have already told you what it is.
Day-knights
and Night-knights
There is a great underground empire where knights live.
There are two kind of knights; Day-knights who tell the truth by
day and lie at night. Night-knights, of course, do it the other way
round. Since it is an underground empire, you can't tell the time
of day by any natural means. But the knights always know whether it's
day or night. So, as a visitor to this strange world, you once meet
a knight who tells you "I'm a day-knight and it's night".
Since you forgot to wind up your watch a few days ago, you don't
know the time. But can you tell from this sentence, whether it's day
or night? And can you tell, whether the knight is a Day-knight or
a Night-knight?
Answer
Age
of the the Prince
A princess is as old as the prince will be when the princess is
twice the age that the prince was when the princess's age was half
the sum of their present ages. If the princess is 40, how old is
the prince?
Answer
Walking
Distance
One hour after David started walking from X to Y, a distance of
45 miles, Lisa started walking along the
same road from Y to X. If David’s walking rate was 3 miles
per hour and Lisa’s was 4 miles per hour, how many miles had
Lisa walked when they met?
Which one is a correct answer
A) 24
B) 23
C) 22
D) 21
E) 19.5
Answer
Have you worked out the answers ?
Are you sure ?
Answer to Box Puzzle
You have to think outside the box
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Answer to 4 men with
Hats
C calls out that he is wearing a black hat. Why is he 100% certain
of the color of his hat ?
After a while, C comes to the realization that he must answer.
This is because D can't answer, and neither can A or B.
D can see C and B, but can't determine his own hat color. B can't
see anyone and also can't determine his own hat color. A is in the
same situation as B, where he can't see anyone and can't determine
his own hat color.
Since A, B, and D are silent, that leaves C. C knows he is wearing
a black hat because if D saw that both B and C were wearing white
hats, then he would have answered. But since D is silent, C knows
that he must be wearing a black hat as he can see that B is wearing
a white hat.
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Answer to the Switches
Problem
Make sure that all light switches are in the "off" position. Flip
the first switch A, and leave it on for about 10 minutes, or so. Then,
turn switch A off. Flip the second switch B on, and go upstairs to
the light bulb.
If the bulb is off, but warm, it is the A switch. If the bulb is
on, it is the B switch. If the bulb is off and cool, it is the C switch
that you haven't turned on yet. You have successfully determined which
switch controls the light bulb, and you have gone up the stairs only
once.
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Answer to the
Twin brothers Puzzle
Point to one of the roads in the fork and ask the following question
to one of the brothers.
"If I ask your brother if this is the correct road to the village
will he say yes or no?"
If he answers is "no" then it is the correct way to the
village.
Think about it -
If the brother you are speaking to is the one who always lies, then
he will say "no" as he knows that his brother who speaks
the truth would anwser "yes". If the brother you are speaking
to is the one who speaks the truth, he will say "no" as
he knows that his brother will lie about it being the correct road.
Either way an answer "no" tells you it is actually the right
road. Similarly if you are pointing to the wrong road you will get
the answer "yes".
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Answer to the Bottle
of Wine Puzzle
A common wrong answer is £1. Now, if the bottle were really
worth a £1, then the wine, being worth £9 more than the
bottle, would be worth £10. Hence the wine and bottle together
would be worth £11.
The correct answer is that the bottle is worth 50 pence and the wine
is worth £9.50. Then the two add up to £10.
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Answer
to the Bear Puzzle
White. If all the walls face south, the house is at
the north pole, and the bear, therefore, is a polar bear.
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Answer to the Ladder
Puzzle
None, the boat rises with the tide.
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Answer to the 4
gallon Bucket Puzzle
Here is a solution:
1) Fill the 3-gallon bucket, dump it into the 5-gallon bucket
2) Fill the 3-gallon bucket, fill the 5-gallon, leaving 1 gallon left
in the 3-gallon bucket
3) Empty the 5-gallon bucket
4) Dump the 1 gallon from the 3-gallon bucket into the 5-gallon bucket
5) Dump one full bucket from the 3-gallon bucket on top of the 1 gallon
in the 5-gallon bucket
You're left with four gallons of water in the 5-gallon bucket.
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Answer to the Third
Word Puzzle
The third word is "language". Here is why:
Think of words ending in 'gry'.
Angry and hungry are two of them.
These two lines are a "red herring" and have nothing to do with the
question being asked.
There are only three words in the English
language.
Notice this line does NOT say there are three words ending in "gry".
What is the third word?
The first word is the
the second word is English
, and the third word is language
.
The word is something that everyone uses
every day.
Language is something that everyone uses every day.
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Answer
to the Knights Problem
This one you are going to have to work out yourself
Answers please to: Contact
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Answer
to the Age of the Prince Problem
Try and work it out yourself. Don't guess - use the information
given to produce a couple of algebraic equations which give you
the solution.
Answers please to: Contact
Walking
distance
Try and work it out yourself. Don't guess - use the information
given to produce a couple of algebraic equations which give you
the solution.
Answers please to: Contact
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