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:
Alone In The Woods Riddle
You are lost and alone in the woods. You stumble across an old cabin, and decide to stay there for the night. You want some heat and light, but the only things you find in the cabin are a candle, an oil lamp and a wood burning stove. You look in your pocket but you only have one match left. What do you light first?
Hint:
Running Through Fields And Woods Riddle
Riddle me this
I run over fields and woods all day. Under the bed at night I sit, never alone. My tongue hangs out, up and to the rear, waiting to be filled in the morning. What am I?
I run over fields and woods all day. Under the bed at night I sit, never alone. My tongue hangs out, up and to the rear, waiting to be filled in the morning. What am I?
Hint:
Pain In The Nails Riddle
Hint:
Nun, Gimel, Heh, And Shin
Nun, gimel, heh, and shin,
See the wooden play piece spin.
Nes gadol hayah shin,
If I'm lucky I will win!
What is it?
See the wooden play piece spin.
Nes gadol hayah shin,
If I'm lucky I will win!
What is it?
Hint:
Invisible At Night Riddle
I fly like a bird of many colors through the sky. I am made with both wood and fire but I do not burn up. You can see me clearly during the day, but I am nearly invisible at night. What am I?
Hint:
Longest Human Nose Riddle
Hint:
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