Little Billy's Calculator
Little Billy has a calculator with 15 buttons. He has 10 keys for 0-9, a key for addition, multiplication, division, and subtraction. Finally, he has an = sign. However, Mark the Meanie messed up the programming on Billy's calculator. Now, whenever Billy presses any of the number keys, it comes up with a random single-digit number. The same goes for the four operations keys (+,-,x, /). So whenever Billy tries to press the + button, the calculator chooses randomly between addition, multiplication, subtraction, and division. The only key left untouched was the = sign.
Now, if Billy were to press one number key, one operation key, then another number key, then the = button, what are the chances the answer comes out to 6?
Now, if Billy were to press one number key, one operation key, then another number key, then the = button, what are the chances the answer comes out to 6?
Hint: Think about how many ways he could possibly get 6.
There is a 4% chance.
There are 16 possible ways to get 6.
0+6
1+5
2+4
3+3
6+0
5+1
4+2
9-3
8-2
7-1
6-0
1x6
2x3
6x1
3x2
6/1
There are 400 possible button combinations.
When Billy presses any number key, there are 10 possibilities; when he presses any operation key, there are 4 possibilities.
10(1st#)x4(Operation)x10(2nd#)=400
16 working combinations/400 possible combinations= .04 or 4% Did you answer this riddle correctly?
YES NO
There are 16 possible ways to get 6.
0+6
1+5
2+4
3+3
6+0
5+1
4+2
9-3
8-2
7-1
6-0
1x6
2x3
6x1
3x2
6/1
There are 400 possible button combinations.
When Billy presses any number key, there are 10 possibilities; when he presses any operation key, there are 4 possibilities.
10(1st#)x4(Operation)x10(2nd#)=400
16 working combinations/400 possible combinations= .04 or 4% Did you answer this riddle correctly?
YES NO
100 Blank Cards Riddle
Someone offers you the following deal:
There is a deck of 100 initially blank cards. The dealer is allowed to write ANY positive integer, one per card, leaving none blank. You are then asked to turn over as many cards as you wish. If the last card you turn over is the highest in the deck, you win; otherwise, you lose.
Winning grants you $50, and losing costs you only the $10 you paid to play.
Would you accept this challenge?
There is a deck of 100 initially blank cards. The dealer is allowed to write ANY positive integer, one per card, leaving none blank. You are then asked to turn over as many cards as you wish. If the last card you turn over is the highest in the deck, you win; otherwise, you lose.
Winning grants you $50, and losing costs you only the $10 you paid to play.
Would you accept this challenge?
Hint: Perhaps thinking in terms of one deck is the wrong approach.
Yes!
A sample strategy:
Divide the deck in half and turn over all lower 50 cards, setting aside the highest number you find. Then turn over the other 50 cards, one by one, until you reach a number that is higher than the card you set aside: this is your chosen "high card."
Now, there is a 50% chance that the highest card is contained in the top 50 cards (it is or it isn't), and a 50% chance that the second-highest card is contained in the lower 50. Combining the probabilities, you have a 25% chance of constructing the above situation (in which you win every time).
This means that you'll lose three out of four games, but for every four games played, you pay $40 while you win one game and $50. Your net profit every four games is $10.
Obviously, you have to have at least $40 to start in order to apply this strategy effectively. Did you answer this riddle correctly?
YES NO
A sample strategy:
Divide the deck in half and turn over all lower 50 cards, setting aside the highest number you find. Then turn over the other 50 cards, one by one, until you reach a number that is higher than the card you set aside: this is your chosen "high card."
Now, there is a 50% chance that the highest card is contained in the top 50 cards (it is or it isn't), and a 50% chance that the second-highest card is contained in the lower 50. Combining the probabilities, you have a 25% chance of constructing the above situation (in which you win every time).
This means that you'll lose three out of four games, but for every four games played, you pay $40 while you win one game and $50. Your net profit every four games is $10.
Obviously, you have to have at least $40 to start in order to apply this strategy effectively. Did you answer this riddle correctly?
YES NO
The Secret Santa Exchange
A group of ten friends decide to exchange gifts as secret Santas. Each person writes his or her name on a piece of paper and puts it in a hat. Then each person randomly draws a name from the hat to determine who has him as his or her secret Santa. The secret Santa then makes a gift for the person whose name he drew.
When it's time to exchange presents, each person walks over to the person he made the gift for and holds his or her left hand in his right hand.
What is the probability that the 10 friends holding hands form a single continuous circle?
When it's time to exchange presents, each person walks over to the person he made the gift for and holds his or her left hand in his right hand.
What is the probability that the 10 friends holding hands form a single continuous circle?
Hint: It's not as difficult as it seems.
It's the number of ways the friends can form a circle divided by the number of ways the names can be drawn out of the hat.
1/10
For a group of n friends, there are n! (n factorial) ways to draw the names out of the hat. Since a circle does not have a beginning and end, choose one person as the beginning and end of the circle. There are now (n-1)! ways to distribute the remaining people around the circle. Thus the probability of forming a single circle is
(n-1)! / n!
Since n! = (n-1)! * n (for n > 1), this can be rewritten as
(n-1)! / (n*(n-1)!)
Factoring out the (n-1)! from the numerator and denominator leaves
1/n
as the probability. Did you answer this riddle correctly?
YES NO
For a group of n friends, there are n! (n factorial) ways to draw the names out of the hat. Since a circle does not have a beginning and end, choose one person as the beginning and end of the circle. There are now (n-1)! ways to distribute the remaining people around the circle. Thus the probability of forming a single circle is
(n-1)! / n!
Since n! = (n-1)! * n (for n > 1), this can be rewritten as
(n-1)! / (n*(n-1)!)
Factoring out the (n-1)! from the numerator and denominator leaves
1/n
as the probability. Did you answer this riddle correctly?
YES NO
Over London Bridge
As I went over London Bridge
I met my sister Jenny
I broke her neck and drank her blood
And left her standing empty
Who is Jenny?
I met my sister Jenny
I broke her neck and drank her blood
And left her standing empty
Who is Jenny?
Hint:
Kidnapping The Queens Son
The Queen lives in a beautiful castle with her only son and a sheep-dog named Sir FooFoo. One day the Queen decides to go out for a spot of tea with some friends. She leaves her eight-year-old son in the care of her trusted servants. The 18 servants are: Harold the health instructor, Griffith the gardener, Tiffany the private tutor, Philip the photographer, Magdalina the maid, Boris the Butler, Geraldo the groundskeeper, Bernadette the barber, Sandy the sweeper, Anastasia the accountant, Constantine the carpenter, Joel the jester, Lucy the launderer, Sadie the seamstress, McKenzie the musical instructor, Lawrence the lawyer, Dorothy the dentist, Devon the doctor, and Surlamina the Secretary of State. When the Queen came home she discovered her son was missing and that he was kidnapped. The Queen came to a conclusion that it must've been one of her servants who kidnapped her son because he was too young to leave on his own and Sir FooFoo was harmless. The Queen interviewed all of her servants to see which one was responsible for the kidnapping. The alibis are as follows: Harold was lifting weights, Griffith was planting roses, Tiffany was checking homework, Philip was taking pictures of the botanical garden, Magdalina was making the beds, Boris was cleaning the banisters, Geraldo was supervising Griffith , Bernadette was trimming Sir FooFoo's hair, Sandy was sweeping in the corners, Anastasia was managing the Queen's affairs, Constantine was building a birdhouse, Joel was coming up with the jokes, Lucy was doing the laundry, Sadie was designing a dress for the Queen, McKenzie was playing the flute, Lawrence was suing the bank, Dorothy was preparing to extract the Queen's tooth when the Queen came home, Devon was examining an x-ray of the Queen's arm, and Surlamina was being a Secretary of State.
Who is the kidnapper?
Who is the kidnapper?
Hint:
Surlamina is responsible for the kidnapping because there is no Secretary of State in a monarchy. It is believed that Surlamina kidnapped the Queen's son because she was not given a real job. Did you answer this riddle correctly?
YES NO
YES NO
Nights Getting Colder
As fall starts to progress along
And nights continue getting colder
This tasty food is something that
Can be eaten off a cob holder
What could it be?
And nights continue getting colder
This tasty food is something that
Can be eaten off a cob holder
What could it be?
Hint:
Zombie Date Riddle
Hint:
All You Can Eat Riddle
Hint:
What Can You Hold In Your Right Hand Riddle
Hint:
7 Candles Riddle
Hint:
7, we asked 'how many candles' not 'how many lit candles' Did you answer this riddle correctly?
YES NO
YES NO
I Drink Milk And Eat Fish Riddle
Hint:
Parents Over For Breakfast
Hint:
7 Ice Cubes Riddle
Hint:
A Single Mother Had A Baby Riddle
Hint:
A Mother Was Killed In A Circular House Riddle
The daughter said she was playing with her dolls, the son said he was playing outside in the garden, the maid said she was dusting corners, the butler said he was watching the son, and the chief said he was baking pies.
Who killed the mother?
Hint:
The Maid; As she said she was dusting the corners and in a round house, there are no corners... Did you answer this riddle correctly?
YES NO
YES NO
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