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
Special Body Ruiddle
Hint:
Generals Armies Riddle
Hint:
Sad Nose Riddle
Hint:
A Ninja Under The Weather
Hint:
The Twelve Inch Nose Riddle
Hint:
Ninja At The Doctor
Hint:
Trapped With The Army
A man got trapped with the army, there were two papers, one said yes the other no. A man in the army said if you get the paper that sees no I will kill you, another man comes in the room sees I put no on both papers. How does he get out of it?
Hint:
He eats one. The man looks at the paper it sees no, so he thought the one the guy ate was yes. Did you answer this riddle correctly?
YES NO
YES NO
In Your Body For Free
What is in your body for free the first and the second time but the third time you have to buy yourself?
Hint:
Your teeth. You get baby teeth and adult teeth as part of the life package, but once you lose those you get to pay for dentures (or scare small children with your sunken face). Did you answer this riddle correctly?
YES NO
YES NO
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
I Walk On 4 Legs In The Morning, 2 Legs At Noon, And 3 Legs At Night
Hint:
The Generals Armies Riddle
Hint:
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
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
Hint:
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