The 100 Seat Airplane
People are waiting in line to board a 100-seat airplane. Steve is the first person in the line. He gets on the plane but suddenly can't remember what his seat number is, so he picks a seat at random. After that, each person who gets on the plane sits in their assigned seat if it's available, otherwise they will choose an open seat at random to sit in.
The flight is full and you are last in line. What is the probability that you get to sit in your assigned seat?
The flight is full and you are last in line. What is the probability that you get to sit in your assigned seat?
Hint: You don't need to use complex math to solve this riddle. Consider these two questions:
What happens if somebody sits in your seat?
What happens if somebody sits in Steve's assigned seat?
The correct answer is 1/2.
The chase that the first person in line takes your seat is equal to the chance that he takes his own seat. If he takes his own seat initially then you have a 100% chance of sitting in your seat, if he takes your seat you have a 0 percent chance. Now after the first person has picked a seat, the second person will enter the plan and, if the first person has sat in his seat, he will pick randomly, and again, the chance that he picks your seat is equal to the chance he picks someone your seat. The motion will continue until someone sits in the first persons seat, at this point the remaining people standing in line which each be able to sit in their own seats. Well how does that probability look in equation form? (2/100) * 50% + (98/100) * ( (2/98) * 50% + (96/98) * ( (2/96) * (50%) +... (2/2) * (50%) ) ) This expansion reduces to 1/2.
An easy way to see this is trying the problem with a 3 or 4 person scenario (pretend its a car). Both scenarios have probabilities of 1/2. Did you answer this riddle correctly?
YES NO
The chase that the first person in line takes your seat is equal to the chance that he takes his own seat. If he takes his own seat initially then you have a 100% chance of sitting in your seat, if he takes your seat you have a 0 percent chance. Now after the first person has picked a seat, the second person will enter the plan and, if the first person has sat in his seat, he will pick randomly, and again, the chance that he picks your seat is equal to the chance he picks someone your seat. The motion will continue until someone sits in the first persons seat, at this point the remaining people standing in line which each be able to sit in their own seats. Well how does that probability look in equation form? (2/100) * 50% + (98/100) * ( (2/98) * 50% + (96/98) * ( (2/96) * (50%) +... (2/2) * (50%) ) ) This expansion reduces to 1/2.
An easy way to see this is trying the problem with a 3 or 4 person scenario (pretend its a car). Both scenarios have probabilities of 1/2. Did you answer this riddle correctly?
YES NO
People Ride On My Back Riddle
I have four legs and a long tail.
I eat oats and hay.
I love to run fast.
I let people ride on my back.
What am I?
I eat oats and hay.
I love to run fast.
I let people ride on my back.
What am I?
Hint:
Riding A Bike Riddle
Hint:
Bank Teller Biking Riddle
Hint:
Elephant On A Bike Riddle
Hint:
Gynecology Beer Riddle
Hint:
Crossing The River Safely Riddle
A man is traveling with a fox and two chickens. If he leaves the fox alone with the chickens, the fox will eat the chickens. He comes to a river and needs to cross it. He finds a small boat that can carry only him and one animal. How does he get himself, the fox and two chickens across the river safely?
Hint:
Take the fox over, return with nothing. Go over with one chicken, return with the fox. Go over with the second chicken, return with nothing. Finally, take the fox over. Did you answer this riddle correctly?
YES NO
YES NO
A Farmer Crossing A River
A farmer has to get a sack of corn, a chicken, and a fox across a river. The farmer is only able to bring one of the above items along with him at a time. The only problem is if he leaves the fox alone with the chicken, the fox will eat the chicken, and if he leaves the chicken along the corn sack, then the chicken will eat the corn sack. How does the farmer get all 3 items across safely?
Hint: The farmer can bring items across the river both ways.The farmer brings the chicken across the river first.
The farmer brings the chicken across. Goes back and brings the fox across, and brings the chicken back with him to the other side of the river and drops off the chicken, then he goes and brings the corn sack across, and finally he goes back for the chicken and brings it across. Did you answer this riddle correctly?
YES NO
YES NO
Even A River Can't Fill It!
Hint:
3 Or 4 Prongs Riddle
These riddles all rhyme
Theyre just like some songs
The next thing to find
Has three or four prongs.
Theyre just like some songs
The next thing to find
Has three or four prongs.
Hint:
Three Rivers Riddle
There are three rivers and after each river lies a grave. A man wants to leave the same number of flowers at each grave and be left with none at the end. However, each time he passes through a river, the number of flowers he has doubles. How many flowers does he have to start with so that he is left with none at the end? And how many does he leave at each grave?
Hint:
This problem has an infinite number of solutions modeled by the equation 8a=7n, where a is the amount of flowers the man starts with and n is the number of flowers he leaves at each grave. The simplest and possibly trivial solution would be to start with 0 flowers and leave 0 flowers at each grave. A more significant solution would be to start with 7 flowers and leave 8 at each grave. Any positive integer multiple of this solution also satisfies the conditions. For example, the man starts with 14 flowers and leaves 16 at each grave; so, 14 doubles to 28, and 28-16= 12; 12 doubles to 24, and 24-16= 8; 8 doubles to 16, and 16-16= 0. The result is the same if the man starts with 21 flowers and leaves 24 flowers at each grave, or starts with 28 and leaves 32. Did you answer this riddle correctly?
YES NO
YES NO
Magic Carpet Ride Riddle
I am a princess who doesn't want to get married,
I run away and pretend I'm delusional,
I meet a boy and a monkey,
I meet the same boy posing as a prince,
He takes me on a magical carpet ride.
I am...?
I run away and pretend I'm delusional,
I meet a boy and a monkey,
I meet the same boy posing as a prince,
He takes me on a magical carpet ride.
I am...?
Hint:
Soldiers On The River
A detachment of soldiers must cross a river. The bridge is broken, the river is deep. What to do? Suddenly the officer-in-charge spots two boys playing in a rowboat by the shore. The boat is so tiny, however, that it can only hold 2 boys or 1 soldier. Still - all the soldiers succeed in crossing the river in the boat. How?
Hint:
First the boys cross the river. One stays ashore while the other brings the boat to the soldiers. A soldier takes the boat back across and the boy that stayed before brings the boat back and picks up the other boy. The boat takes the two boys back and one remains while the other boy returns the boat to the soldiers. This is repeated until all of the soldiers are on the opposite side of the river. Did you answer this riddle correctly?
YES NO
YES NO
Rings Tell My Age Riddle
Hint:
Rings Of Age Riddle
People climb me, cut me and burn me, they show me no respect! My rings are not of gold, but they do tell my age?
Hint:
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