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**j4tt****Member**- Registered: 2005-02-21
- Posts: 14

find the next letter of the sequence......

ze, te, tw, th, fo, fi, si, se, ei,...........

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**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,558

... that almost makes sense

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman

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**j4tt****Member**- Registered: 2005-02-21
- Posts: 14

Great problems.......

my teacher gave me this problem that

If there is an empty pond and you keep adding water such that if you enter x liters on first day, you enter 2x the second day, 4x on the third and so on.. It takes 30 days to fill a pond. How long will it takes to fill 1/8th the pond..????

*Last edited by j4tt (2005-02-23 01:36:55)*

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**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,558

Well, let's see, on the first day it has x liters, on the second day x(1+2), third day x(1+2+4) fourth day x(1+2+4+8), etc... Am I on the right track? Any geniuses out there?

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman

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**j4tt****Member**- Registered: 2005-02-21
- Posts: 14

........................SOLUTION.....................................................

work backwards.. that is if a pond fills in 30 days, it will takes 29 days to fill half of it(doubles each day). this means that it will takes 28 day to fill a quarter of the pond and 27 days to fill 1/8th of it...............

*Last edited by j4tt (2005-02-23 02:05:40)*

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**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,558

Hmmm ... what you enter doubles ... So on the first day it has x liters, on the second day 3x, on the third day 7x, ... after a few days it does get close enough to doubling. In fact you could say it always doubles, except it is always 1x short

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman

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**j4tt****Member**- Registered: 2005-02-21
- Posts: 14

I said that you enter x liters of water the first day 2x on the second day and 4x on the second day. I did'nt say there TOTAL!!!! (it mean you keep doubling the amount of water you enter in the pond each day with respect to the amount of water entered the previous day irrespective of the ammount of water in the pond)

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**j4tt****Member**- Registered: 2005-02-21
- Posts: 14

Well Another problem not so hard but just thinking...........

There are 52 cards in a pack of cards. If you turn any 10 cards upside down and place them back(upside down) and give them a good shuffel so that the card are at random. Now from the top of the pile pick 10 cards. Using those 10 cards how can you make the same number of card upside down in each pile, without looking into the rest of the pile....????????

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**Roraborealis****Member**- Registered: 2005-03-17
- Posts: 1,594

I haven't got a clue for that one, could you tell me the answer?

School is practice for the future. Practice makes perfect. But - nobody's perfect, so why practice?

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**jam-pot****Member**- Registered: 2005-04-20
- Posts: 142

you burn em all in a pit of scorpians ??

well i tryed

the allmighty spatula * want a tip* dont eat yellow snow: the meaning of life is a number and that number is 1

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**Roraborealis****Member**- Registered: 2005-03-17
- Posts: 1,594

I guess that's all that counts.

School is practice for the future. Practice makes perfect. But - nobody's perfect, so why practice?

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**mathsyperson****Guest**

Take the pile of 10 cards, turn it over. Done.

**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,558

So, the two piles have 42 and 10 cards each. There are 10 upside-down cards mixed up in them, and you don't know if the pile of 10 cards has no upside-downs, 1 upside-down, or, freakishly, 10 upside down cards.

If, for example, there are 9 upside-downs in the 42, then there will be 1 upside-down in the 10

Turning the 10-pile upisde down will result in 9 upside-downs, matching the pile of 42.

Does it work for all combinations?

Wow, good party trick.

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**jam-pot****Member**- Registered: 2005-04-20
- Posts: 142

um errr ok*looks away*

well anyways i think my method works aswell and scorpians burning and pits are a good combination for a party yeah!

well not that good if you burn your armpit with a scorpian???

muahahahahahaha the allmight spatula

the allmighty spatula * want a tip* dont eat yellow snow: the meaning of life is a number and that number is 1

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