The Same Number Of Ones Riddle
Hint:
The Three Digit Number Riddle
Hint:
Finding The Number Riddle
What number am I? I am a three digit number. My tens digit is five more than my ones digit. My hundreds digit is eight less than my tens digit.
Hint:
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
The Even Number Riddle
Hint:
Digits From 1 To 9 Riddle
Hint:
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
Positive Numbers
Hint:
Only Self-Enumerating Number
Hint:
Four. The number four has four letters, making it self-enumerating. Did you answer this riddle correctly?
YES NO
YES NO
Even Number Riddle
Hint:
Cents In A Nickel Riddle
Hint:
3 Tens And 1 One Riddle
Hint:
Both Digits Are The Same Riddle
I am an odd number. Both of my digits are the same. I am the missing number in this pattern: 45, 50, __, 60. What am I?
Hint:
Not An Even Number Riddle
Hint:
My Ones Digit Is 1 Riddle
Hint:
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