Little Billy's Calculator
Little Billy has a calculator with 15 buttons. He has 10 keys for 0-9, a key for addition, multiplication, division, and subtraction. Finally, he has an = sign. However, Mark the Meanie messed up the programming on Billy's calculator. Now, whenever Billy presses any of the number keys, it comes up with a random single-digit number. The same goes for the four operations keys (+,-,x, /). So whenever Billy tries to press the + button, the calculator chooses randomly between addition, multiplication, subtraction, and division. The only key left untouched was the = sign.
Now, if Billy were to press one number key, one operation key, then another number key, then the = button, what are the chances the answer comes out to 6?
Now, if Billy were to press one number key, one operation key, then another number key, then the = button, what are the chances the answer comes out to 6?
Hint: Think about how many ways he could possibly get 6.
There is a 4% chance.
There are 16 possible ways to get 6.
0+6
1+5
2+4
3+3
6+0
5+1
4+2
9-3
8-2
7-1
6-0
1x6
2x3
6x1
3x2
6/1
There are 400 possible button combinations.
When Billy presses any number key, there are 10 possibilities; when he presses any operation key, there are 4 possibilities.
10(1st#)x4(Operation)x10(2nd#)=400
16 working combinations/400 possible combinations= .04 or 4% Did you answer this riddle correctly?
YES NO
There are 16 possible ways to get 6.
0+6
1+5
2+4
3+3
6+0
5+1
4+2
9-3
8-2
7-1
6-0
1x6
2x3
6x1
3x2
6/1
There are 400 possible button combinations.
When Billy presses any number key, there are 10 possibilities; when he presses any operation key, there are 4 possibilities.
10(1st#)x4(Operation)x10(2nd#)=400
16 working combinations/400 possible combinations= .04 or 4% Did you answer this riddle correctly?
YES NO
The Cheap Mp3 Player
My MP3 player is cheap 'n' nasty and has now broken: it is stuck on 'Shuffle'. In this mode it starts with whatever track you put it on, but then plays tracks in a random order. The only restriction is it never plays a song that's already been played that day.
I purchased my favourite murder mystery book in audio format, and put the first 6 chapters on my MP3 player. (Each chapter is exactly 1 track.) There's nothing else on my player at the moment. What is the probability that I will hear the 6 chapters in order as I listen today, without having to change tracks at all? (Obviously, I will ensure it plays chapter 1 first.)
The next day I empty the player before putting on the next 6 chapters. This time I also transfer a CD of mine with 11 songs on. I don't mind songs coming in between the chapters of my book, as long as the chapters are in order. What's the probability of that happening now?
I purchased my favourite murder mystery book in audio format, and put the first 6 chapters on my MP3 player. (Each chapter is exactly 1 track.) There's nothing else on my player at the moment. What is the probability that I will hear the 6 chapters in order as I listen today, without having to change tracks at all? (Obviously, I will ensure it plays chapter 1 first.)
The next day I empty the player before putting on the next 6 chapters. This time I also transfer a CD of mine with 11 songs on. I don't mind songs coming in between the chapters of my book, as long as the chapters are in order. What's the probability of that happening now?
Hint:
With only 6 tracks on the player:
The first chapter has been set to play first. The probability of the next 5 chapters playing in order is 1/5! = 1/120.
With the music on the player as well:
Seeing as I don't care about when the music plays, it doesn't change anything. The answer is still 1/120. Did you answer this riddle correctly?
YES NO
The first chapter has been set to play first. The probability of the next 5 chapters playing in order is 1/5! = 1/120.
With the music on the player as well:
Seeing as I don't care about when the music plays, it doesn't change anything. The answer is still 1/120. Did you answer this riddle correctly?
YES NO
Blue Eyes Riddle
Both of my parents have brown eyes, as do I. My brother and my wife have blue eyes. Using the simple brown-blue model (two genes; a brown gene dominates blue gene), what are the chances of my first child having blue eyes?
Hint: Given my brother's blue eyes, what are the odds on my pair of eye-color genes?
1 in 3.
Since my brother has blue eyes (bb), both of my parents carry one brown and one blue gene (Bb). The three possibilities for my genotype, equally likely, are BB, Bb, and bB. Thus, there is a 2/3 chance that I carry a blue gene.
If I carry a blue gene, there is a 50% chance I will pass it on to my first child (and, obviously, 0% if I carry two brown genes).
Since my child will certainly get a blue gene from my wife, my gene will determine the eye color.
Multiplying the probabilities of those two independent events, there is a chance of 1/2 x 2/3 = 1/3 of my passing on a blue gene. Did you answer this riddle correctly?
YES NO
Since my brother has blue eyes (bb), both of my parents carry one brown and one blue gene (Bb). The three possibilities for my genotype, equally likely, are BB, Bb, and bB. Thus, there is a 2/3 chance that I carry a blue gene.
If I carry a blue gene, there is a 50% chance I will pass it on to my first child (and, obviously, 0% if I carry two brown genes).
Since my child will certainly get a blue gene from my wife, my gene will determine the eye color.
Multiplying the probabilities of those two independent events, there is a chance of 1/2 x 2/3 = 1/3 of my passing on a blue gene. Did you answer this riddle correctly?
YES NO
Dressed In All Black
A man dressed in all black is walking down a country lane. Suddenly, a large black car without any lights on comes round the corner and screeches to a halt. How did the car know he was there?
Hint:
The Quietest Whimper
I talk, but I do not speak my mind
I hear words, but I do not listen to thoughts
When I wake, all see me
When I sleep, all hear me
Many heads are on my shoulders
Many hands are at my feet
The strongest steel cannot break my visage
But the softest whisper can destroy me
The quietest whimper can be heard.
What am I?
I hear words, but I do not listen to thoughts
When I wake, all see me
When I sleep, all hear me
Many heads are on my shoulders
Many hands are at my feet
The strongest steel cannot break my visage
But the softest whisper can destroy me
The quietest whimper can be heard.
What am I?
Hint:
Four Times To Infinity
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
The Female Head Riddle
There are four in a deck of cards
And it is a size of bed
In countries with a monarchy
This is the female head
What is this?
And it is a size of bed
In countries with a monarchy
This is the female head
What is this?
Hint:
Dinner At Thanksgiving
This food is something you'll need
It is normally yellow
And the kernels are maizes seed
What is it?
Hint:
I'll See You Rot Riddle
Hint:
Share The Same Name Riddle
but mean two different things
one goes up and down
and the other spins
while one can make you sick
the other you cannot touch
you have heard of me before
whether you know it or not
you know our name
just give it a thought
One is a messenger
the other is not
One gives you a reading
The other helps the Oracle
What are we?
Hint:
Mercury (Messenger is Hermes, or in Latin it is Mercury) Did you answer this riddle correctly?
YES NO
YES NO
Three Doors Riddle
Hint:
Hunter Polar Bear Riddle
He sees a bear and is about to shoot it.
The bear grabs his gun and eats it.
The hunter runs away one mile east.
He then walks one mile north and gets back to his camp and changes his underwear.
What color was the bear?
Hint:
He starts at at the NORTH POLE.
This means he walks south for a mile, but when he heads east for a mile he's just walking round in part of a circle, and stays one mile from the North pole. Therefore he only has to walk a mile north to get back!
So what color is the bear? It has to be a polar bear, so it's WHITE! Did you answer this riddle correctly?
YES NO
This means he walks south for a mile, but when he heads east for a mile he's just walking round in part of a circle, and stays one mile from the North pole. Therefore he only has to walk a mile north to get back!
So what color is the bear? It has to be a polar bear, so it's WHITE! Did you answer this riddle correctly?
YES NO
A Woman Is Sitting In Her Hotel Room Riddle
Hint:
I Wish Yesterday Was Tomorrow Riddle
On which day did the teacher say this?
Hint:
It depends. The grammar is intentionally misleading; "yesterday was" is generally considered incorrect, but is still something people say. The speaker in the riddle may mean "I wish yesterday were tomorrow" or "I wish yesterday had been tomorrow", etc. So:
I wish yesterday (Wednesday) had been what tomorrow (Friday) will be = today is Thursday.
I wish yesterday had been Thursday so tomorrow would be Friday = today is any day!
I wish yesterday (Tuesday) had been [today's] tomorrow (Thursday), so that today (Wednesday) would be Friday (day after desired yesterday).
I wish yesterday (Saturday) would be [today's] tomorrow, then today (Sunday) would be Friday. Did you answer this riddle correctly?
YES NO
I wish yesterday (Wednesday) had been what tomorrow (Friday) will be = today is Thursday.
I wish yesterday had been Thursday so tomorrow would be Friday = today is any day!
I wish yesterday (Tuesday) had been [today's] tomorrow (Thursday), so that today (Wednesday) would be Friday (day after desired yesterday).
I wish yesterday (Saturday) would be [today's] tomorrow, then today (Sunday) would be Friday. Did you answer this riddle correctly?
YES NO
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