Riddle me this, Riddle me that!

It has six faces and twelve edges too
It has six colors one of which is blue.
It can twist and turn, keeping you amused
Until all is whole you may be confused

What is it?
 
Alright, a hard maths puzzle, Enjoy:

A very long hallway has 1000 doors numbered 1 to 1000; all doors are initially closed. One by one, 1000 people go down the hall: the first person opens each door, the second person closes all doors with even numbers, the third person closes door 3, opens door 6, closes door 9, opens door 12, etc. That is, the n th person changes all doors whose numbers are divisible by n . After all 1000 people have gone down the hall, which doors are open and which are closed?

Trololololololo..... :D
 
I used my calendar to calculate the first 20 doors. I found that all the square numbers will be open, meaning: 1, 4, 9, 16, 25, 36, 49, 64, 81 and 100 will be open. Correct?

Edit: I see now that there is 1000 doors...
Open doors:
1,4,9,16,25,36,49,64,81,100,121,144,169,196,225,256,289,324,361,400,441,484,529,576,625,676,729,784,841,900,961

Hope that's all...
 
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FriedPet said:
I used my calendar to calculate the first 20 doors. I found that all the square numbers will be open, meaning: 1, 4, 9, 16, 25, 36, 49, 64, 81 and 100 will be open. Correct?

Edit: I see now that there is 1000 doors...
Open doors:
1,4,9,16,25,36,49,64,81,100,121,144,169,196,225,256,289,324,361,400,441,484,529,576,625,676,729,784,841,900,961

Hope that's all...
Click to expand...

Correct Neb! Well done on getting that one, I thought it was a real b****!

You're up.
 
StaggerLee said:
Correct Neb! Well done on getting that one, I thought it was a real b****!

You're up.
Click to expand...

It was! At first glance I ignored the riddle as it looked too difficult, but as I was studying last night I thought this looked more interesting!;)

I found this one on the internet, too lazy to figure it out.

Chris Mercer informed me that in Germany there are calendars made of wooden blocks for very bright kids.
There are two six sided dice, and by choosing which face is displayed for the two of these, all possible monthly dates (from 01, 02, …, to 29, 30, 31) can be displayed; note the single digit dates must start with a 0.

Your job is to write one digit (from 0, 1, 2, …, 8, 9) on each face of the two dice so that this can be done. Good luck!
 
FriedPet said:
It was! At first glance I ignored the riddle as it looked too difficult, but as I was studying last night I thought this looked more interesting!;)

I found this one on the internet, too lazy to figure it out.

Chris Mercer informed me that in Germany there are calendars made of wooden blocks for very bright kids.
There are two six sided dice, and by choosing which face is displayed for the two of these, all possible monthly dates (from 01, 02, …, to 29, 30, 31) can be displayed; note the single digit dates must start with a 0.

Your job is to write one digit (from 0, 1, 2, …, 8, 9) on each face of the two dice so that this can be done. Good luck!
Click to expand...

Both dice need 0 to 3 on i.e. 0,1,2,3. That leaves 2 empty sides on each die. On the one die, you can write 5 and 6 and on the other you can write 7 and 8. If you place the first die upside-down on the 6, it acts as a 9, and if you place the second die upside-down on the 7 is acts a 4. If it makes you happier it can be a 4 that acts a 7 when upside down, but either way, it works.
 
StaggerLee said:
Both dice need 0 to 3 on i.e. 0,1,2,3. That leaves 2 empty sides on each die. On the one die, you can write 5 and 6 and on the other you can write 7 and 8. If you place the first die upside-down on the 6, it acts as a 9, and if you place the second die upside-down on the 7 is acts a 4. If it makes you happier it can be a 4 that acts a 7 when upside down, but either way, it works.
Click to expand...

That sounds about right:) Well done, looks like it was easier than I thought. Give us your best shot!!
 
Surely only one dice needs a zero since you don't have a 00 date but you do get 11, 22, 33 so the dice needs to be 0, 1, 2, 3, 4, 5 and 1, 2 ,3, 6, 7, 8 with six doubling as 9 also?
 
Ike_009 said:
Surely only one dice needs a zero since you don't have a 00 date but you do get 11, 22, 33 so the dice needs to be 0, 1, 2, 3, 4, 5 and 1, 2 ,3, 6, 7, 8 with six doubling as 9 also?
Click to expand...

My bad, Eugene picked up a flaw in your answer :/
 
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