3 Gallon Jug And 5 Gallon Jug
The problem is to fill one of the jugs with exactly 4 gallons of water. How do you do it?
You've got to defuse a bomb by placing exactly 4 gallons (15 L) of water on a sensor. The problem is, you only have a 5 gallon (18.9 L) jug and a 3 gallons (11 L) jug on hand! This classic riddle, made famous in Die Hard 3.
Hint:
Fill the 5-jug up completely. There will be, of course, 5 gallons in the 5-jug. You must fill all the gallons up to the top, otherwise you don't actually know how much you have.
Use the water from the 5-jug to fill up the 3-jug. You're left with 3 gallons in the 3-jug and 2 gallons in the 5-jug.
Pour out the 3-gallon jug. You're left with nothing in the 3-jug and 2 gallons in the 5-jug.
Transfer the water from the 5-jug to the three jug. You're left with 2 gallons in the 3-jug. And nothing in the 5-jug.
Fill up the 5-jug completely. You now have 2 gallons in the 3-jug and 5 in the 5-jug. This means that there is 1 gallon (3.8 L) of space left in the 3-jug.
Use the water from the 5-jug to fill up the 3-jug. Fill up the last gallon of space in the 3-jug with the water from the 5-jug. This leaves you with 3 gallons in the 3-jug, and 4 gallons in the 5-jug.
Fill the 3-jug completely with water. You now have 3 gallons (11.4 L) of water.
Transfer this water into the 5-jug. You now have nothing in the 3-jug, and 3 gallons (11.4 L) in the 5-jug.
Re-fill the 3-jug with water. You now have 3 gallons (11.4 L) in the 3-jug and 3 gallons in the 5-jug.
Fill the 5-jug with water from your 3-jug. You now have 1 gallon (3.8 L) in the 3-jug and 5 gallons (18.9 L) in the 5-jug. This is because, in the last step, you only had 2 gallons (7.6 L) of space left over, so you could only pour 2 gallons.
Pour out the 5-jug and refill it with your 1 gallon. You now have nothing in the 3-jug and 1 gallon in the 5-jug
Fill up the 3-jug. You now have 3 gallons (11.4 L) in the 3-jug and 1 in the 5-jug.
Transfer the 3 gallons (11.4 L) of water into the 5-jug to end up with 4 gallons (15.1 L). Simply pour over your three gallons into the 5-jug, which only had 1 gallon (3.8 L) in it previously. 1+3=4, and a successfully defused bomb. Did you answer this riddle correctly?
YES NO
Use the water from the 5-jug to fill up the 3-jug. You're left with 3 gallons in the 3-jug and 2 gallons in the 5-jug.
Pour out the 3-gallon jug. You're left with nothing in the 3-jug and 2 gallons in the 5-jug.
Transfer the water from the 5-jug to the three jug. You're left with 2 gallons in the 3-jug. And nothing in the 5-jug.
Fill up the 5-jug completely. You now have 2 gallons in the 3-jug and 5 in the 5-jug. This means that there is 1 gallon (3.8 L) of space left in the 3-jug.
Use the water from the 5-jug to fill up the 3-jug. Fill up the last gallon of space in the 3-jug with the water from the 5-jug. This leaves you with 3 gallons in the 3-jug, and 4 gallons in the 5-jug.
Fill the 3-jug completely with water. You now have 3 gallons (11.4 L) of water.
Transfer this water into the 5-jug. You now have nothing in the 3-jug, and 3 gallons (11.4 L) in the 5-jug.
Re-fill the 3-jug with water. You now have 3 gallons (11.4 L) in the 3-jug and 3 gallons in the 5-jug.
Fill the 5-jug with water from your 3-jug. You now have 1 gallon (3.8 L) in the 3-jug and 5 gallons (18.9 L) in the 5-jug. This is because, in the last step, you only had 2 gallons (7.6 L) of space left over, so you could only pour 2 gallons.
Pour out the 5-jug and refill it with your 1 gallon. You now have nothing in the 3-jug and 1 gallon in the 5-jug
Fill up the 3-jug. You now have 3 gallons (11.4 L) in the 3-jug and 1 in the 5-jug.
Transfer the 3 gallons (11.4 L) of water into the 5-jug to end up with 4 gallons (15.1 L). Simply pour over your three gallons into the 5-jug, which only had 1 gallon (3.8 L) in it previously. 1+3=4, and a successfully defused bomb. Did you answer this riddle correctly?
YES NO
You Walk Into Dr Dolittle Room Riddle
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What Was New, Is New Again Riddle
Hint:
I Am First A Fraud Or A Trick Riddle
Hint:
Fear He Who Hides Behind One Riddle
Hint:
Dog Refreshments Riddle
Hint:
Driving At Midnight Riddle
I was driving at midnight on Jan. 31. It was freezing cold in New York. I was on an isolated unpaved road when my car battery went dead. The headlights went off, and I coasted to a stop. There were no moon or stars out, and no human-made lights visible. Yet I clearly saw a mouse cross the road, and could tell that it was brown, not gray. How is this possible?
Hint:
Lakes And Boats Riddle
There is a lake with shores A and B. Two motorboats M and N are standing on the opposite sides (A and B respectively). M leaves A and N leaves B and start moving with constant speeds. They meet for the first time 500 yards away from A. After touching the shores, they return back to the previous shore point without taking any break. This time they meet at 300 yards away from B.
Can you determine how wide the lake is? What is the relation between the speeds of boats?
Can you determine how wide the lake is? What is the relation between the speeds of boats?
Hint:
When the boats meet for the first time, they have sailed a combined distance that is equal to one length of the lake. When they meet the second time, they have sailed 3 lengths. The elapsed time and the distance for each is three times.
When they meet for the second time, the boat M has sailed 500 x 3 = 1500 yards. Now, this is 300 yards longer than the length of the lake, it must be 1200 yards wide.
The ration between the speed of boat M and boat N is equal to the ratio of the distance that they have sailed before they meet the first time. Did you answer this riddle correctly?
YES NO
When they meet for the second time, the boat M has sailed 500 x 3 = 1500 yards. Now, this is 300 yards longer than the length of the lake, it must be 1200 yards wide.
The ration between the speed of boat M and boat N is equal to the ratio of the distance that they have sailed before they meet the first time. Did you answer this riddle correctly?
YES NO
Building A Bar Riddle
Roy Smith wanted a new bar. He was such an eccentric old bar owner that he wanted a bar in which all fours walls faced south. After much thought, the builders managed to construct just such a bar. How did they do it?
Hint:
Stabbed In The Leg Riddle
Let's say you are being stabbed in the leg by a knife constantly. What do you do to stop getting stabbed?
Hint:
Stop saying it.
Get it?
Let's SAY "you are being stabbed in the leg by a knife" constantly. So if you stop saying it, you won't be stabbed anymore...? Did you answer this riddle correctly?
YES NO
Get it?
Let's SAY "you are being stabbed in the leg by a knife" constantly. So if you stop saying it, you won't be stabbed anymore...? Did you answer this riddle correctly?
YES NO
Th One Called Coney Riddle
There is one called Madagascar
But it isnt a movie
And if you want a good hot dog
Go to the one called Coney.
Where could this be?
But it isnt a movie
And if you want a good hot dog
Go to the one called Coney.
Where could this be?
Hint:
The Bee And The Bikes Riddle
Two bikes are traveling toward each other at a constant speed of 10 mph. When the bike are 20 miles apart, a bee flies from the front wheel of one of the bikes toward the other bike at a constant speed of 25 mph. As soon as it reaches the front wheel of the other bike, it immediately turns around and flies at 25 mph toward the first bike. It continues this pattern until the two bikes smush the bee between the two front tires.
How far did the bee travel?
How far did the bee travel?
Hint:
25 miles.
The easiest way to think about this is to consider the time. The bikes will take 1 hour to touch, given that they start 20 miles apart and are each traveling toward each other at 10 mph.
Therefore the bee is buzzing back and forth at 25 mph for 1 hour. Did you answer this riddle correctly?
YES NO
The easiest way to think about this is to consider the time. The bikes will take 1 hour to touch, given that they start 20 miles apart and are each traveling toward each other at 10 mph.
Therefore the bee is buzzing back and forth at 25 mph for 1 hour. Did you answer this riddle correctly?
YES NO
Keeping Tempeture Riddle
Hint:
Presidential Promises Riddle
Ronald has a rare opportunity to meet the President of the United States. During his visit the president gives him a gift but tells Ronald he is never to sell it unless he sees the president again. Ronald consents, but the president dies later that year. Years later a man offers to buy the Presidents gift for $1000. Ronald agrees and exchanges the gift for 20 crisp $50 bills. Did he keep his promise?
Hint:
Yes. The president was Ulysses S. Grant, who died in 1885 and whose face has been on the $50 bill since 1913. He saw the president on the bills before he made the exchange. Did you answer this riddle correctly?
YES NO
YES NO
Running Windows Riddle
Name a five letter word which has three consonants all the same and two different vowels. Every now and then you see this while running a Windows 95/98 on your PC.
Hint:
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