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
Sad Nose Riddle
Hint:
A Ninja Under The Weather
Hint:
The Twelve Inch Nose Riddle
Hint:
Ninja At The Doctor
Hint:
The Number Four Be Half Of Five Riddle
Hint:
IV, the Roman numeral for four, which is “half” (two letters) of the word five. Did you answer this riddle correctly?
YES NO
YES NO
The Correct Number Riddle
Hint:
121
Explanation
Tables consist of squares of the number from 4 to 12.
11^2 = 121. Did you answer this riddle correctly?
YES NO
Explanation
Tables consist of squares of the number from 4 to 12.
11^2 = 121. Did you answer this riddle correctly?
YES NO
Find Those Missing Numbers Riddle
In the attached figure, you can find two missing numbers. Can you analyze the pattern and find those missing numbers?
Hint:
The number missing on the left is 8 and the one on right is 7.
Explanation:
The pattern:
The number in the center of triangle is the square root of the sum of the numbers sitting outside on the corners.
Thus,
10 + 22 + 4 = 36
Square Root of 36 = 6
In the same manner:
10 + 42 + 12 = 64
Square Root of 64 = 8
12 + 22 + 15 = 49
Square Root of 49 = 7 Did you answer this riddle correctly?
YES NO
Explanation:
The pattern:
The number in the center of triangle is the square root of the sum of the numbers sitting outside on the corners.
Thus,
10 + 22 + 4 = 36
Square Root of 36 = 6
In the same manner:
10 + 42 + 12 = 64
Square Root of 64 = 8
12 + 22 + 15 = 49
Square Root of 49 = 7 Did you answer this riddle correctly?
YES NO
I Am A 3 Digit Number Between 400 And 800 Riddle
I am a 3 digit number between 400 and 800. My digits add up to 15. My ten's digit is twice my hundreds digit. What number am i?
Hint:
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
The Noisy Barking Dog
Hint:
The Nosy Old Woman
My neighbors think I'm a nosy old woman, but today I witnessed a murder. I was looking out my window when I saw something through the window of the apartment building opposite me. A man was in the middle of murdering a woman. The strange thing was, after he finished strangling her, he turned around and our eyes met. It was eerie. Then he pointed at me and kept staring at me for a minute or two. All the time he was staring at me, his finger kept moving. I called the police a few minutes ago and they told me I will have to go down to the police station and give a statement tomorrow. I'm sure they will catch him. I saw his face very clearly.
What do you think the murderer was waving his finger at?
What do you think the murderer was waving his finger at?
Hint:
The murderer was counting the windows to see which floor the old woman was on. He is coming to kill her. Did you answer this riddle correctly?
YES NO
YES NO
Alex And The New Neighbor Riddle
So Alex and his friends are hanging out in his front yard one day, and they notice the house next to them has been sold and somebody new has moved in. Alex and his friends decide they want to greet the person the next day.
So it is the next day. Before they leave, Alex's mother asks them what they are doing, but since Alex despises his mom and doesn't like to talk to her, he just answer with "we are going to the new neighbor, can you leave us alone?" She says "who is the new neighbor." But Alex tells her to shut up and they leave.
They ring the doorbell, the neighbor comes outside, and Alex says hello and then the neighbors name. So what is the neighbors name?
So it is the next day. Before they leave, Alex's mother asks them what they are doing, but since Alex despises his mom and doesn't like to talk to her, he just answer with "we are going to the new neighbor, can you leave us alone?" She says "who is the new neighbor." But Alex tells her to shut up and they leave.
They ring the doorbell, the neighbor comes outside, and Alex says hello and then the neighbors name. So what is the neighbors name?
Hint:
The new neighbors name is 'Who.' ...When the mom SUPPOSEDLY asked "Who is the new neighbor?", she wasn't asking; she was making a statement. "Who is [the name of] the new neighbor." Did you answer this riddle correctly?
YES NO
YES NO
Longest Human Nose Riddle
Hint:
Neck But No Head Riddle
Hint:
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