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joelove
Joined: 12 May 2011

Posted: Sat Dec 08, 2012 8:30 am Post subject: A geek math question. 


Why not. My older brother is a mathematician. We were looking at this book of problems the other day. I guess it is hard to do math notation here but, anyway, the question was, raise 50 to the power of n. Then, let's say 50 is raised to the power of 999. I believe that was the question. Then what are the last 1000 digits of 50 to the 999th power? It will surely be 999 zeroes at the end. Another brother informs me, and he knows stuff. Number theory. I got to study more.
Sorry, I did say it was a geek math question. 

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Moondoggy
Joined: 07 Jun 2011

Posted: Sat Dec 08, 2012 4:28 pm Post subject: Re: A geek math question. 


joelove wrote: 
Why not. My older brother is a mathematician. We were looking at this book of problems the other day. I guess it is hard to do math notation here but, anyway, the question was, raise 50 to the power of n. Then, let's say 50 is raised to the power of 999. I believe that was the question. Then what are the last 1000 digits of 50 to the 999th power? It will surely be 999 zeroes at the end. Another brother informs me, and he knows stuff. Number theory. I got to study more.
Sorry, I did say it was a geek math question. 
It's 5 followed by 999 zeros. 

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Hugo85
Joined: 27 Aug 2010

Posted: Sat Dec 08, 2012 5:17 pm Post subject: 


(50)^n = (5^n)*(10^n) and the (10^n) will provide a zero for each power to which it is raised. (5^n)'s last digit is always a five so it won't give more zeros.. 

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Moondoggy
Joined: 07 Jun 2011

Posted: Sat Dec 08, 2012 7:37 pm Post subject: 


Hugo85 wrote: 
(50)^n = (5^n)*(10^n) and the (10^n) will provide a zero for each power to which it is raised. (5^n)'s last digit is always a five so it won't give more zeros.. 
If you're still in college I suggest you take "discrete mathematics" which covers basics of set theory, algorithms, elementary number theory, combinatorial enumeration, discrete probability, graphs and trees, etc..
Anyways this is for you.
50 = 5 * 10
50 ^ 999 = (5 ^ 999) * (10 ^ 999)
5 ^ n always ends in 5, if n > 0.
10 ^ 999 has 999 zeros.
I have a question for the op. What does this math question have to do teaching ESL? 

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joelove
Joined: 12 May 2011

Posted: Sat Dec 15, 2012 12:24 am Post subject: 


Oh it has nothing to do with teaching ESL, but this is an off topic forum, so we are allowed to post nonsense. I knew it was 5 plus many zeroes. 5 times 5 time 5 and so on, always a 5. Dunno why I bother posting this. Beer. Yay beer.
Got any better ones? Will try to think or find one. Brother is not well, the math guy, but he still knows stuff. 

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