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 Blue And Red Dice Riddle
Timothy and Urban play a game with two dice. But they do not use the numbers. Some of the faces are painted red and the others blue. Each player throws the dice in turn. Timothy wins when the two top faces are the same color. Urban wins when the colors are different. Their chances are even.
The first die has 5 red faces and 1 blue face. How many red and how many blue are there on the second die?
The first die has 5 red faces and 1 blue face. How many red and how many blue are there on the second die?
Hint:
Each die has 6 faces. When two dice are thrown, there are 36 equally possible results. For chances to be even, there must be 18 ways of getting the same color on top. Let X be the number of red faces on the second die. We have: 18 = 5X + 1(6 - X)
X = 3
The second die must have 3 red faces and 3 blue faces. Did you answer this riddle correctly?
YES NO
X = 3
The second die must have 3 red faces and 3 blue faces. Did you answer this riddle correctly?
YES NO
If A Door Number Fitter Riddle
In a new hotel containing 100 rooms, Tom was hired to paint the numbers from 1-100 on the doors. How many times will Tom have to paint the number 8?
Hint:
The answer is 20. Many people have been guessing anywhere from 9 to 19, but the correct answer is 20. Did you answer this riddle correctly?
YES NO
YES NO
Five Apples Riddle
There were five women sitting in a room. In the same room there was a basket with five apples in it. Each woman took an apple, but one apple still remained in the basket. How could this be?
Hint:
The fifth woman took the entire basket, with the apple still in it. Did you answer this riddle correctly?
YES NO
YES NO
Rivers With No Water Riddle
Hint: I represent an area of land or sea.
All Things Devours Riddle
This thing all things devours, birds, beasts, trees, flowers.
Gnaws iron, bites steel,
Grinds hard stone to meal.
Slays kings, ruins towns,
and beats high
Mountains Down
Gnaws iron, bites steel,
Grinds hard stone to meal.
Slays kings, ruins towns,
and beats high
Mountains Down
Hint: I'm free but also priceless.
Longest Human Nose Riddle
Hint:
Participating In A Race
Hint: It's not first place.
If you answer that you are first, then you are absolutely wrong! If you overtake the second person and you take his place, you are second! Did you answer this riddle correctly?
YES NO
YES NO
It Follows A River While Standing Still
Hint:
2 Fathers And 2 Sons Riddle
Two fathers and two sons sat down to eat eggs for breakfast. They ate exactly three eggs, each person had an egg. The riddle is for you to explain how?
Hint:
One of the 'fathers' is also a grandfather. Therefore the other father is both a son and a father to the grandson.
In other words, the one father is both a son and a father. Did you answer this riddle correctly?
YES NO
In other words, the one father is both a son and a father. Did you answer this riddle correctly?
YES NO
What Kind Of Room Has No Doors Or Windows Riddle
Hint:
The Turkey Crossing The Road
Hint:
Make It Rain
Hint:
A Base With No Room
What has a base but no room, a key but no lock, you can enter but you can't get into it? What is it?
Hint:
Running With No Legs?
Hint:
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