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
100 Offices Riddle
A new medical building containing 100 offices had just been completed. Mark was hired to paint the numbers 1 to 100 on the doors. How many times will Mark have to paint the number nine?
Hint:
Did you say three? The correct answer is twenty (29, 39, and so on). Did you answer this riddle correctly?
YES NO
YES NO
Dial 666
Hint:
2 4 12 48 240 Riddle
Hint:
240. To get the number, multiply the previous number in the series by its position. 48 is in the 5th position, so 48 � 5 = 240 Did you answer this riddle correctly?
YES NO
YES NO
Five Hundred Riddle
Hint:
Equals Eight Riddle
Hint:
Mirror one of the threes and put it and the other three together to get an eight. Did you answer this riddle correctly?
YES NO
YES NO
Four And Five Riddle
Hint:
Twenty In The Pool
Hint:
Match The Number Of Letters
This can be a little tricky if you misread the riddle. There's a little known fact in this once you've found the answer. Also being that the answers are limited, it's recommended to challenge yourself and begin the timer to solve this in under 30 seconds.
Spell me out and I am the number of a month in which I also match the number of letters exactly of this month. What am I?
Hint: There are only 12 months
How Can It Be True Riddle
How can it be? Half of nine is one plus three?
How can it be true? Half of eleven is 4 plus 2?
Now can you see? Half of 3 is also 3.
How can it be true? Half of eleven is 4 plus 2?
Now can you see? Half of 3 is also 3.
Hint:
Ancient Roman numerals. IX - "Cut" it in half and you get IV
XI- "Cut" it in half and you get VI
III- "Cut" it in half and you get also III
Did you answer this riddle correctly?
YES NO
XI- "Cut" it in half and you get VI
III- "Cut" it in half and you get also III
Did you answer this riddle correctly?
YES NO
The Number Pattern Riddle
Hint:
31131211131221.
Each line, excluding the first, describes the one before it.
1
11 <---describes 1st line, read as "one 1"
21 <---describes 2nd line, read as "two 1's"
1211 <---describes 3rd line, read as "one 2 two 1's" Did you answer this riddle correctly?
YES NO
Each line, excluding the first, describes the one before it.
1
11 <---describes 1st line, read as "one 1"
21 <---describes 2nd line, read as "two 1's"
1211 <---describes 3rd line, read as "one 2 two 1's" Did you answer this riddle correctly?
YES NO
The Four Digit Number Riddle
Can you find the four digit number in which the first digit is one fourth of the last digit, the second digit is 6 times the first digit, and the third digit is the second digit plus 3?
Hint:
Combination Value Riddle
The letters A through H can be assigned the following values to make all the equations true. Find the right combination of letter values.
Values: 1, 4, 5, 7, 9, 14, 16, 21
C + F = G
A + C = F
B + G = D
B + E = H
D + F = H
Values: 1, 4, 5, 7, 9, 14, 16, 21
C + F = G
A + C = F
B + G = D
B + E = H
D + F = H
Hint:
Counting In Binary Riddle
Hint:
Digits From 1 To 9 Riddle
Hint:
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