# 5 billion | 28 Jul 2009

Discussion in '\$1 Daily Competition' started by shabbir, Jul 28, 2009.

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If you multiply together the number of fingers on every person's left-hands? (For the purposes of this exercise, thumbs count as fingers, for five fingers per hand) how long the number would be assuming 5 billion people on earth.

2. ### KshiteejNew Member

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0.
It would only take one person to have no fingers on their left hand to make it zero as anything multiplied by 0 is 0.

3. ### KshiteejNew Member

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If all 5 billion people have 5 fingers on their left hand then the answer is 5^5 billion else answer will be 0 if any of this 5 billion people have no fingers on his/her left hand.

4. ### mayjuneNew Member

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Point 1 : In the above post, user has posted two answers in one post, using an If Else statement. So either the last answer in the post should be counted. Or it should be considered invalid, as this is not there in the rule - "only one answer per post."

Point 2 : Question is not clear, 5 fingers per person for only who have thumb or otherwise?

5. ### SaswatPadhi~ Б0ЯИ Τ0 С0δЭ ~

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The only assumption here is we have 5 billion ppl on earth.
We don't know if we have exceptions like someone without fingers on left hand etc ..

There can be a lot of cases like some 1 has 1 finger, 2 fingers, 3 fingers .. no fingers etc..
And, I don't think it's possible to consider all of them.

So.. i think the answer will be :

The length of the number is
= 5 billion * log(base 10) 5
= 5 * 10^9 * 0.69897000433601880478626110527551
= 3494850022 digits

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5 fingers are considered and not 4 fingers and 1 thumb.

Many are close or I must say quite close but still no perfect answers.

7. ### xpi0t0sMentor

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Zero, because there is at least one person with a missing left hand.

8. ### xpi0t0sMentor

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So the answer is 1. because the length of the number zero is 1.

Or if you just want the length of 5^5000000000, that's easy enough too, with a little help from logs and a calculator:
5^5000000000=10^(log(5^5000000000))
=10^(5000000000*log(5))
5000000000*log(5)=3494850021.6800940239313055263775

so the length of 5^5e9 is 3494850022

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Bingo

10. ### SaswatPadhi~ Б0ЯИ Τ0 С0δЭ ~

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I thought we will end up with no current answer.
'coz every1 answered 0, but shabbir needed the length.

Congratz xpi0t0s. :happy:

11. ### SaswatPadhi~ Б0ЯИ Τ0 С0δЭ ~

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lol .. i meant correct answer, but typed "current" somehow :rofl:

12. ### mayjuneNew Member

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nice one shabbir, you tricked us into it

13. ### mayjuneNew Member

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nice one shabbir, you tricked us into it congrats xp

14. ### rik625New Member

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Kis type ka question tha yeh yaar?? :crazy:
... Kuch samaj main nahi aaya

LOL...Question to door ki baat hai..answer bhi bouncer gaya...LOL

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Please use English as medium of communication.

16. ### mayjuneNew Member

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LOL, what is the length of this string ?
"HELLO"

5 right?

So what is the length of string 0?
1

why number of fingers = 0?
Cause one of them will have no fingers in left hand, hence anything multiplied by 0 is = 0.
Length of 0 = 1
Hence Ans = 1

17. ### rik625New Member

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Allright Shabir...My aplogies.

mayjune..thanks for explaining..I think if i read it more than times..I would surely get it...

18. ### mayjuneNew Member

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No problem..