Some simple question

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Bericht 13-07-'05, 06:46

Anonymous

Some simple question

Hey people I just thought of something,,

If you count up by 1, till 1,000,000,00 how many times till you encounter 9 ?

And how do you calculate that ? not just by counting right ??

Thanks in advance
Omhoog

Bericht 13-07-'05, 07:59

Elmo

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Re: Some simple question

Why are you posting in English on a Dutch science forum? :shock:
Never underestimate the predictability of stupidity...
Omhoog

Bericht 13-07-'05, 09:34

Ard

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Re: Some simple question

one plus one plus one plus one plus one plus one plus one plus one plus one equals nine.. Just by counting and you will have only one time change of nine....... Voor de rest. Inderdaad, waarom in het Engels op een Nederlands Forum :shock:
Omhoog

Bericht 13-07-'05, 10:19

NASE

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Re: Some simple question

Why are you posting in English on a Dutch science forum?   :shock:
Who knows. We can still try to helf him, won't we.

What I think.

I think that you can best take series of 99. That serie appears a lot. The first time from 0 untill 99. and the second time from 100 until 199. Now you can calculate how many times zou can find that serie. That you can find a number for the number of nines below 1000. You can ten do the same thing with 1000. From 1000 till 1999 we have the some number. And so on. The only thing you have to do is don't forget that when the numbers start whit a nine. That rule doesn't wordk perfectly.
Omhoog

Bericht 15-07-'05, 03:55

mo

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Re: Some simple question

Calculator schreef:Hey people I just thought of something,,

If you count up by 1, till 1,000,000,00 how many times till you encounter 9 ?

And how do you calculate that ? not just by counting right ??

Thanks in advance
wat bedoelt die gast met till you encounter 9 ? is het hoeveel keer je het getal 9 tegenkomt?
Omhoog

Bericht 15-07-'05, 10:42

Revelation

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Re: Some simple question

Yes, mo².

Well, from one 1 to 100, it is 9-19-29-39-49-59-69-79-89-90-91-92-93-94-95-96-97-98-99 (two here). So that makes 20.

From 100 to 200, 200 to 300, 300 to 400, 400 to 500, 500 to 600, 600 to 700, 700 to 800, 800 to 900 it is the same.

From 900-1000 you will have 100 more. (900 included)

So you will have 20 * 9= 180 180 + 120 = 300.



From 1000 to 2000 etc it will be the 300 we found. So you can keep going on like that until you reach your number. Watch the 9000-10000 one, you will always have an increase with (for 9000-10000 that will be 1000).
“Quotation is a serviceable substitute for wit.” - Oscar Wilde
Omhoog
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