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Topic: Math question  (Read 3715 times)

articx

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Math question
« on: February 10, 2011, 12:37:51 pm »
Do you know the answer to this question below?


There are seven amoebae in a jar. They double every minute. If it takes 40 minutes to fill the jar, how long would it take to fill the jar half-way?

Valerie1979

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Re: Math question
« Reply #1 on: February 10, 2011, 03:14:58 pm »
 if they double every minute it would be 1/2 full at 39 minutes

mc1962

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Re: Math question
« Reply #2 on: February 11, 2011, 08:26:32 am »
20 minutes?  I think that is the answer- because it dosent matter whats inside the jar, if it takes 40 minutes to fill the jar then it should take 20 minutes to get half way.  Just a guess.  :binkybaby:

cubarican210

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Re: Math question
« Reply #3 on: February 11, 2011, 09:19:13 am »
Do you know the answer to this question below?


There are seven amoebae in a jar. They double every minute. If it takes 40 minutes to fill the jar, how long would it take to fill the jar half-way?

If I got it right It would be at 39 minutes.

At 40 minutes there would be a total of 7,696,581,394,432 Amoeba in the jar
At 39 minutes there would be 3,848,290,697,216 Amoeba which is half of the total number. Now the question is how large is the jar? Lol!

oonamas

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Re: Math question
« Reply #4 on: February 11, 2011, 09:45:14 am »
20 minutes?  I think that is the answer- because it dosent matter whats inside the jar, if it takes 40 minutes to fill the jar then it should take 20 minutes to get half way.  Just a guess.  :binkybaby:
That's not the answer because the amoeba are growing exponentially. When the amoeba double the new amoeba then also start doubling and so forth, so the jar starts out with the amoeba population growing more slowly and ends with it growing very rapidly, get it?

U2BMATH

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Re: Math question
« Reply #5 on: February 11, 2011, 10:03:50 am »
Stands to reason that 39 minutes is the correct answer. Because at 39 minutes, assuming the jar is half full, it will double in size on minute 40, thus making the jar full.

SCarter984

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Re: Math question
« Reply #6 on: February 11, 2011, 10:08:19 am »
This is far too deep for me but I'll take a shot.  20 minutes?  Are you giving the correct answer at some point?

kezalter

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Re: Math question
« Reply #7 on: February 11, 2011, 11:34:42 am »
if they double every minute it would be 1/2 full at 39 minutes

Good call.  I was initially thinking I'd have to do the actual maths to pinpoint it but obviously this is much better.

Valerie1979

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Re: Math question
« Reply #8 on: February 11, 2011, 04:41:13 pm »
This is far too deep for me but I'll take a shot.  20 minutes?  Are you giving the correct answer at some point?

why am i thinking we just answered someone's math homework or something -- maybe the person that posted this didn't even know the answer~!

articx

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Re: Math question
« Reply #9 on: February 11, 2011, 05:44:54 pm »
why am i thinking we just answered someone's math homework or something -- maybe the person that posted this didn't even know the answer~!
This was a bonus question that appeared on a quiz in my copyrights class. I turned in the quiz and was told the answer before posting the question here.

This is far too deep for me but I'll take a shot.  20 minutes?  Are you giving the correct answer at some point?
Yes I will. The correct answer is 39 minutes.

Valerie1979

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Re: Math question
« Reply #10 on: February 12, 2011, 06:01:15 am »
why am i thinking we just answered someone's math homework or something -- maybe the person that posted this didn't even know the answer~!
This was a bonus question that appeared on a quiz in my copyrights class. I turned in the quiz and was told the answer before posting the question here.

This is far too deep for me but I'll take a shot.  20 minutes?  Are you giving the correct answer at some point?
Yes I will. The correct answer is 39 minutes.

:)  thanks!  :) 

mrsbluesmith

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Re: Math question
« Reply #11 on: February 12, 2011, 07:39:25 am »
20 minutes?  I think that is the answer- because it dosent matter whats inside the jar, if it takes 40 minutes to fill the jar then it should take 20 minutes to get half way.  Just a guess.  :binkybaby:

I agree.  I think 20 minutes is the correct answer,

articx

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Re: Math question
« Reply #12 on: February 12, 2011, 11:56:40 am »
20 minutes?  I think that is the answer- because it dosent matter whats inside the jar, if it takes 40 minutes to fill the jar then it should take 20 minutes to get half way.  Just a guess.  :binkybaby:

I agree.  I think 20 minutes is the correct answer,
At 39 minutes, the jar is half full. In the next minute, they double, which means the jar would be filled at 40 minutes. 39 minutes is the correct answer.

Brittney030208

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Re: Math question
« Reply #13 on: February 12, 2011, 07:10:11 pm »
39 is the right answer.

It is very simply explained many times lol. Love the question!

hephzibahpotoak

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Re: Math question
« Reply #14 on: February 13, 2011, 02:53:22 am »
what is the answer?

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