The Last Cookie Riddle
Mike and James are arguing over who gets the last cookie in the jar, so their dad decides to create a game to settle their dispute. First, Mike flips a coin twice, and each time James calls heads or tails in the air. If James gets both calls right, he gets the last cookie. If not, Mike picks a number between one and six and then rolls a die. If he gets the number right, he gets the last cookie. If not, James picks two numbers between one and five, then spins a spinner with numbers one through five on it. If the spinner lands on one of James' two numbers, he gets the last cookie. If not, Mike does.
Who is more likely to win the last cookie, Mike or James? And what is the probability that person wins it?
Who is more likely to win the last cookie, Mike or James? And what is the probability that person wins it?
Hint: Their dad is a very smart person.
Believe it or not, both Mike and James have a 1/2 chance of winning.
James wins if:
-he calls both coin flips right = 1/2 x 1/2 = 1/4
OR
-he does not call both coin flips right, Mike does not call the die roll correctly, and he guesses the number on the spinner right = 3/4 x 5/6 x 2/5 = 30/120 = 1/4
1/4 + 1/4 = 1/2
Mike wins if:
-James does not call both coin flips right and he calls the die roll correctly = 3/4 x 1/6 = 3/24 = 1/8
OR
-James does not call both coin flips right, he does not call the die roll correctly, and Mike does not guess the number on the spinner right = 3/4 x 5/6 x 3/5 = 45/120 = 3/8
1/8 + 3/8 = 1/2
Of course, dad could have just flipped a coin Did you answer this riddle correctly?
YES NO
James wins if:
-he calls both coin flips right = 1/2 x 1/2 = 1/4
OR
-he does not call both coin flips right, Mike does not call the die roll correctly, and he guesses the number on the spinner right = 3/4 x 5/6 x 2/5 = 30/120 = 1/4
1/4 + 1/4 = 1/2
Mike wins if:
-James does not call both coin flips right and he calls the die roll correctly = 3/4 x 1/6 = 3/24 = 1/8
OR
-James does not call both coin flips right, he does not call the die roll correctly, and Mike does not guess the number on the spinner right = 3/4 x 5/6 x 3/5 = 45/120 = 3/8
1/8 + 3/8 = 1/2
Of course, dad could have just flipped a coin Did you answer this riddle correctly?
YES NO
A 10 Foot Rope Ladder
A 10 foot rope ladder hangs over the side of a boat with the bottom rung on the surface of the water. The rungs are one foot apart, and the tide goes up at the rate of 6 inches per hour. How long will it be until three rungs are covered?
Hint:
Building A Wall
Hint:
An Absentminded Philosopher Riddle
An absentminded philosopher forgot to wind up the only clock in his house. He had no radio, television, telephone, internet, or any other means of ascertaining the time. He therefore decided to travel by foot to his friend's house, a few miles down a straight desert road. He stayed there for the night and when he came back home the following morning, he was able to set his clock to the correct time. Assuming the philosopher always walks at the same speed, how did he know the exact time upon his return? Note: this is not a trick question. The Philosopher did not bring anything to his friend's house, nor did he bring anything back with him on his trip home.
Hint: We can assume that the journey to his friend's and back took exactly the same amount of time.
He Philosopher winds the grandfather clock to a random time right before leaving, 9:00 for example. Although this is not the right time, the clock can now be used to measure elapsed time. As soon as he arrives at his friend's house, the Philosopher looks at the time on his friend's clock. Let's say the time is 7:15. He stays overnight and then, before leaving in the morning, he looks at the clock one more time. Let's say the time is now 10:15 (15 hours later). When the Philosopher arrives home, he looks at his grandfather clock. Let's say his clock reads 12:40. By subtracting the time he set it to when he left (9:00) from the current time (12:40) he knows that he has been gone for 15 hours and 40 minutes. He knows that he spent 15 hours at his friends house, so that means he spent 40 minutes walking. Since he walked at the same speed both ways, it took him 20 minutes to walk from his friend's home back to his place. So the correct time to set the clock to in this example would therefore be 10:15 (the time he left his friend's house) + 20 minutes (the time it took him to walk home) = 10:35. Did you answer this riddle correctly?
YES NO
YES NO
Elf Transportation Riddle
Hint:
Share The Same Name Riddle
We share the same name,
but mean two different things
one goes up and down
and the other spins
while one can make you sick
the other you cannot touch
you have heard of me before
whether you know it or not
you know our name
just give it a thought
One is a messenger
the other is not
One gives you a reading
The other helps the Oracle
What are we?
but mean two different things
one goes up and down
and the other spins
while one can make you sick
the other you cannot touch
you have heard of me before
whether you know it or not
you know our name
just give it a thought
One is a messenger
the other is not
One gives you a reading
The other helps the Oracle
What are we?
Hint:
Mercury (Messenger is Hermes, or in Latin it is Mercury) Did you answer this riddle correctly?
YES NO
YES NO
A Grandfather Clock Riddle
A grandfather clock chimes the appropriate number of times to indicate the hour, as well as chiming once at each quarter hour. If you were in another room and heard the clock chime just once, what would be the longest period of time you would have to wait in order to be certain of the correct time? Assuming you had absolutely no clue what time it was.
Hint:
You would have to wait 90 minutes between 12:15 and 1:45. Once you had heard seven single chimes, you would know that the next chime would be two chimes for 2 oclock.
In order for daylight savings time to come into play, you would have to manually set the clock back, which unless you did it with your eyes closed would indicate the time to you. Did you answer this riddle correctly?
YES NO
In order for daylight savings time to come into play, you would have to manually set the clock back, which unless you did it with your eyes closed would indicate the time to you. Did you answer this riddle correctly?
YES NO
How Many Days In A Year Riddle
If a year has 365 days and a leap year has 366 days, then according to time, how many days in a year would have 24 hours?
Hint:
363 days. When daylight savings time starts, that day would consist of 23 hours of time, because the clock advances an hour and when the daylight savings time ends, that day would consist of 25 hours of time, because the clock goes back to the standard time. Did you answer this riddle correctly?
YES NO
YES NO
Three People At A Bus Stop Riddle
You're driving down the road in your car on a wild and stormy night. The weather is like a hurricane, with heavy rains, high winds, and lightning flashing constantly. While driving, you come across a partially-covered bus stop, and you can see three people waiting for a bus:
1. An old woman who looks as if she is about to die.
2. An old friend who once saved your life.
3.The perfect partner you have been dreaming about (your soulmate).
Knowing that you only have room for one passenger in your car (its a really small car), which one would you choose to offer a ride to? And why?
1. An old woman who looks as if she is about to die.
2. An old friend who once saved your life.
3.The perfect partner you have been dreaming about (your soulmate).
Knowing that you only have room for one passenger in your car (its a really small car), which one would you choose to offer a ride to? And why?
Hint:
I would give the car keys to my old friend, and let him take the old woman to the hospital. Then I would stay behind and wait for the bus with the partner of my dreams. Did you answer this riddle correctly?
YES NO
YES NO
A Train Leaves From Halifax Riddle
A train leaves from Halifax, Nova Scotia heading towards Vancouver, British Columbia at 120 km/h. Three hours later, a train leaves Vancouver heading towards Halifax at 180 km/h. Assume theres exactly 6000 kilometers between Vancouver and Halifax. When they meet, which train is closer to Halifax?
Hint:
Both trains would be at the same spot when they meet therefore they are both equally close to Halifax. Did you answer this riddle correctly?
YES NO
YES NO
A Woman Gave Birth To Two Sons Riddle
A woman gave birth to two sons who were born on the same hour of the same day of the same year but were not twins. How is this possible?
Hint:
A Blind Man Named Grandpa Riddle
A blind man named Grandpa has boarded a train to his home. He underwent a successful operation on his eyes and the doctor asked him to open the bandages after 6 hours. On his train journey, he opened the bandages and within seconds commit suicide by jumping off the train.
Why did Grandpa commit suicide despite his eye operation was successful?
Why did Grandpa commit suicide despite his eye operation was successful?
Hint:
When blind man "Grandpa" opened his bandages, the train must be passing through the dark tunnel. The man thought he was still blind and hence commit suicide. Did you answer this riddle correctly?
YES NO
YES NO
A Prisoner Escaped From A Prison Riddle
A prisoner escaped from a prison and began to make a dash on foot. He ran for about 3 miles with intermittent stops to catch his breath until he saw a police car coming towards him. Instead of turning in the opposite direction and making a run for it, the man ran towards the police car briefly before turning and running into a nearby woods to hide. Why did the man run towards the police car?
Hint:
The man was more than halfway across a bridge when he spotted the police car, so the quickest way to leave the bridge was to run towards the police car and then turn and run into the woods to hide. Did you answer this riddle correctly?
YES NO
YES NO
I Go Up And I Go Down Towards The Sky And The Ground Riddle
I go up and I go down,
towards the sky and the ground.
I'm present and past tense too,
Let's go for a ride, me and you.
What am I?
towards the sky and the ground.
I'm present and past tense too,
Let's go for a ride, me and you.
What am I?
Hint:
A Woman Had 2 Sons Riddle
A woman had two sons who were born on the same hour of the same day of the same year. But they were not twins. How could this be so?
Hint:
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