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Imagine you have a million of lightbulbs, in numerical numbers, from 1,2,3,4.... to 1 000 000.
All the lightbulbs are OFF....
When i press the switch of the first lightbulb then ALL THE LIGHTBULBS WILL TURN ON.
When i press the switch of the second lightbulb then ALL THE MULTIPLES OF 2 WILL CHANGE, (ie. if they are on then they go off, if they are off, they turn on.)
When i press the switch of the third lightbulb then ALL THE MULTIPLES OF 3 WILL CHANGE (ie. if they are on then they go off, if they are off, they turn on)
And so on........
UNTIL you get to the 1,000,000th swtich...
At the end.. which lightbulbs are On?
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w/o even really thinking about it
the first one?
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Umm, I think it's that brain but that would be one hell of an easy riddle :/
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United Kingdom10597 Posts
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It's not too hard. Think about it. All numbers with an even number of factors will be off, those with an odd number will be on. All primes will be off. 1 will be on.
As a result, only square numbers will be on. 1,4,9,16,25, etc. etc.
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Here's a better one:
Three woman go to their favorite restaurant and each order some food that costs £30 overall. So they each give £10 to the waiter who then gives it to the manager. The manager however decides to give £5 back to the women as a good will gesture since the women have been such loyal customers over the years. Now the waiter thinks he can make some money out of this so he secretely takes £2 for himself and only gives £1 back to each women.
This means each woman has payed £9 each, having originally payed £10 and gotten £1 back.
The waiter has £2 thus the overall money payed is 3x9 + 2 = £29.
So where'd the extra pound go?
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With the way the riddle's said, you'd think that it would be that when the 1 000 000th switch is turned on, all the multiples of 1 000 000 would change, and that would mean only the last one.
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On June 17 2005 13:20 Pistachio wrote:
Here's a better one:
Three woman go to their favorite restaurant and each order some food that costs £30 overall. So they each give £10 to the waiter who then gives it to the manager. The manager however decides to give £5 back to the women as a good will gesture since the women have been such loyal customers over the years. Now the waiter thinks he can make some money out of this so he secretely takes £2 for himself and only gives £1 back to each women.
This means each woman has payed £9 each, having originally payed £10 and gotten £1 back.
The waiter has £2 thus the overall money payed is 3x9 + 2 = £29.
So where'd the extra pound go?
Old One. Order of Operations.
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What is the next number in this sequence....
1,2,4,8,16,31
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On June 17 2005 13:15 LTT wrote:
It's not too hard. Think about it. All numbers with an even number of factors will be off, those with an odd number will be on. All primes will be off. 1 will be on.
As a result, only square numbers will be on. 1,4,9,16,25, etc. etc.
That is....CORRECT!. Im thinking in other difficult ones, ill post them later.
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On June 17 2005 13:23 BigBalls wrote:
What is the next number in this sequence....
1,2,4,8,16,31
There are a few that could be. You are most likely thinking about the maximum number of regions formed in a circle by connecting straight lines between n points on the circle. In which case it would be, 57,99,163
It could just as well be 32,62,124,248,496,992 which are the divisors of 992. Although that one is finite... (Similarly divisors of 496)
60,116,224,432 for the expansion of 1/(1-2x+x^5).
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BigBalls, are you serious? I don't want to spend hours on a joke 
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On June 17 2005 13:29 LTT wrote:Show nested quote +On June 17 2005 13:23 BigBalls wrote:
What is the next number in this sequence....
1,2,4,8,16,31 There are a few that could be. You are most likely thinking about the maximum number of regions formed in a circle by connecting straight lines between n points on the circle. In which case it would be, 57,99,163
you bitch lol
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you beat me to the squares answer, then you answer that one grrrrrrr
ok, here's one that ltt is prohibited from answering
1
11
21
1211
111221
312211
what is the next element in the sequence
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lol i just noticed it was renamed capslock topic omfg ahahaha
someone make it math riddles or something
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Beyonder
Netherlands15103 Posts
On June 17 2005 13:33 BigBalls wrote:
lol i just noticed it was renamed capslock topic omfg ahahaha
someone make it math riddles or something
:O
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EPT
