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
The Prime Number Riddle
Two hundred people in an auditorium are asked to think of a single digit number from 1 to 9 inclusive and write it down. All those who wrote down a prime number are now asked to leave. Ninety people remain behind in the hall. How many of these are expected to have written down an odd number?
Hint: Remember that 1 is not a prime number.
Those that remain behind must have written {1,4,6,8,9} and from this only {1,9} are odd. The probability of an odd number is thus 2/5.
Expected number of odds is 2/5 * 90 = 36 Did you answer this riddle correctly?
YES NO
Expected number of odds is 2/5 * 90 = 36 Did you answer this riddle correctly?
YES NO
A Man Was Outside Taking A Walk When It Began To Rain
A man was outside taking a walk when it began to rain. He did not have an umbrella and he wasn't wearing a hat. His clothes were soaked, yet not a single hair on his head got wet. How could this happen?
Hint:
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:
9 Letters Riddle
What word in English has 9 letters that keeps producing another word when you remove any one letter from it (goes on up to a single letter)?
Hint:
Startling - starting - staring - string - sting - sing - sin - in - I. Did you answer this riddle correctly?
YES NO
YES NO
What Can You Hold In Your Right Hand Riddle
Hint:
Christmas Vehicular Homicide Riddle
Vehicular homicide was committed on Dad's mom by a precipitous darlin, what Christmas Carol is this?
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
7 Ice Cubes Riddle
I have 7 ice cubes inside a cup of water how many ice cubes do I have left after putting the cup in the freezer?
Hint:
A Girl Was Crying Riddle
A girl was crying because her boyfriend left her, she broke a bottle and a chair... what broke first?
Hint:
In The Jar Riddle
A jar is put on the edge of the table in such a way that half of it is left hanging. What is in the jar?
Hint:
A Girl Unlocks Her Boyfriend's Phone Riddle
A girl unlocks her boyfriend's phone. She found three different contacts having the same name "LOVE". 1st "Love" is the daughter of his dad's dad daughter in law. 2nd "Love" is the mother of his mother and 3rd one is she herself.
Hows the 1st contact is related to the 2nd one?
Hows the 1st contact is related to the 2nd one?
Hint:
I Have 6 Eggs
Hint: The eggs aren't specified.
You See A Boat Riddle
You see a boat filled with people. It has not sunk, but when you look again, you don't see a single person there. Why?
Hint:
There Was A Plane Crash Riddle
Hint:
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