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If n is a positive integer and k = 5.1 x 10^n , what is the value of k https://gmatclub.com/forum/ifnisapositiveintegerandk51x10nwhatisthevalueofk93857.html 
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Author:  shaneforu [ 08 May 2010, 08:45 ] 
Post subject:  If n is a positive integer and k = 5.1 x 10^n , what is the value of k 
If n is a positive integer and k = 5.1 x 10^n , what is the value of k ? (1) 6,000 < k < 500,000 (2) k^2 = 2.601 * 10^9 OPEN DISCUSSION OF THIS QUESTION IS HERE: ifnisapositiveintegerandk51x10nwhatisthe110589.html 
Author:  cipher [ 08 May 2010, 11:05 ] 
Post subject:  Re: If n is a positive integer and k = 5.1 x 10^n , what is the value of k 
shaneforu wrote: I guess you forget to complete the question.. and I think the question is asking value of K \(K = 5.1 * 10^n\) 1. Sufficient, we can easily see K = 51000, and n = 4, As when n = 3 K will be = 5.1 * 10 ^3 = 5100 and when n = 5 then K = 5.1 * 10 ^5 = 510000 2. Sufficient , \(K = \sqrt{sqr2.601} * \sqrt{sqr(10 ^9)}\) Hence D 
Author:  shaneforu [ 09 May 2010, 19:35 ] 
Post subject:  Re: If n is a positive integer and k = 5.1 x 10^n , what is the value of k 
nitishmahajan wrote: shaneforu wrote: I guess you forget to complete the question.. and I think the question is asking value of K \(K = 5.1 * 10^n\) 1. Sufficient, we can easily see K = 51000, and n = 4, As when n = 3 K will be = 5.1 * 10 ^3 = 5100 and when n = 5 then K = 5.1 * 10 ^5 = 510000 2. Sufficient , \(K = \sqrt{sqr2.601} * \sqrt{sqr(10 ^9)}\) Hence D from 2) Can't K be = +51 X 10^4 or 51 X 10^4 there are two possible values here 
Author:  cipher [ 10 May 2010, 00:41 ] 
Post subject:  Re: If n is a positive integer and k = 5.1 x 10^n , what is the value of k 
shaneforu wrote: nitishmahajan wrote: shaneforu wrote: I guess you forget to complete the question.. and I think the question is asking value of K \(K = 5.1 * 10^n\) 1. Sufficient, we can easily see K = 51000, and n = 4, As when n = 3 K will be = 5.1 * 10 ^3 = 5100 and when n = 5 then K = 5.1 * 10 ^5 = 510000 2. Sufficient , \(K = \sqrt{sqr2.601} * \sqrt{sqr(10 ^9)}\) Hence D from 2) Can't K be = +51 X 10^4 or 51 X 10^4 there are two possible values here st2 can be written as \(K = \sqrt{2.601} * \sqrt{(10 ^9)}\) = \(\sqrt{2601} * \sqrt{(10 ^6)} = 51 * (10 ^3) = 5.1 * (10^4) [ As K = 5.1 * 10 ^n ]\) Now if n =4 then K will always be positive and thats why we ruled out the ve value of K 
Author:  dixitraghav [ 16 May 2010, 09:53 ] 
Post subject:  Re: If n is a positive integer and k = 5.1 x 10^n , what is the value of k 
D both the equations are sufficient to find the value of K 
Author:  ying [ 08 Jun 2010, 21:30 ] 
Post subject:  Re: If n is a positive integer and k = 5.1 x 10^n , what is the value of k 
nitishmahajan wrote: Now if n =4 then K will always be positive and thats why we ruled out the ve value of K Even if n<0, k is always > 0. 
Author:  Bunuel [ 24 Dec 2016, 07:48 ] 
Post subject:  Re: If n is a positive integer and k = 5.1 x 10^n , what is the value of k 
If n is a positive integer and k = 5.1 * 10^n, what is the value of k ? As n is a positive integer then k could be: 51, 510, 5,100, 51,000, ... Also note that no matter the value of n, k is always a positive number. (1) 6,000 < k < 500,000 > only one number from above is in this range: 51,000. Sufficient. (2) k^2 = 2.601 * 10^9 > we can solve quadratics to get two values of k positive and negative, but since given that k is positive then only the positive value of k will be valid. Sufficient. Answer: D. OPEN DISCUSSION OF THIS QUESTION IS HERE: ifnisapositiveintegerandk51x10nwhatisthe110589.html 
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