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A list of measurements in increasing order is 4, 5, 6, 8, 10 and x. If [#permalink]
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23 Sep 2010, 11:45
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A list of measurements in increasing order is 4, 5, 6, 8, 10 and x. If the median of these measurements is 6/7 times their arithmetic mean, what is the value of x? A. 16 B. 15 C. 14 D. 13 E. 12 Attachment:
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Re: A list of measurements in increasing order is 4, 5, 6, 8, 10 and x. If [#permalink]
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23 Sep 2010, 11:56
A list of measurements in increasing order is 4, 5, 6, 8, 10 and x. If the median of these measurements is 6/7 times their arithmetic mean, what is the value of x?A. 16 B. 15 C. 14 D. 13 E. 12 {4, 5, 6, 8, 10, x} Median would be the average of two middle terms > \(median=\frac{6+8}{2}=7\); \(mean=\frac{4+5+6+8+10+x}{6}=\frac{33+x}{6}\); Given: \(median=\frac{6}{7}*mean\) > \(7=\frac{6}{7}*\frac{33+x}{6}\) > \(x=16\). Answer: A.
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Re: A list of measurements in increasing order is 4, 5, 6, 8, 10 and x. If [#permalink]
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24 Sep 2010, 00:20
4, 5, 6, 8, 10 and x => median is : (6+8)/2 = 7 mean is = (4+5+6+8+10+x)/6 = (33+x)/6 since the median is 6/7 times of mean ==> 7= 6/7(33+x)/6 ==> 16



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A list of measurements in increasing order is 4,5,6,8,10,x. If the med [#permalink]
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20 Jul 2016, 01:21
A list of measurements in increasing order is 4,5,6,8,10,x. If the median of these measurements is 6/7 times their arithmetic mean, What is the value of x?
A.16 B.15 C.14 D.13 E.12
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Re: A list of measurements in increasing order is 4,5,6,8,10,x. If the med [#permalink]
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20 Jul 2016, 01:49
bimalr9 wrote: A list of measurements in increasing order is 4,5,6,8,10,x. If the median of these measurements is 6/7 times their arithmetic mean, What is the value of x?
A.16 B.15 C.14 D.13 E.12
This question was locked. Given a list of measurements in increasing order is 4,5,6,8,10,x and then x is the greatest number in the list. Median = (6+8)/2 ( since is even number of series) AM = mean=(4+5+6+8+10+x)/6 = (33+x)/6 {(33+x) /6 }*6/7 =7 x=4933=16. Correction option is A.



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Re: A list of measurements in increasing order is 4, 5, 6, 8, 10 and x. If [#permalink]
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20 Jul 2016, 01:59



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A list of measurements in increasing order is 4, 5, 6, 8, 10 and x. If [#permalink]
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23 Jul 2016, 00:53
udaymathapati wrote: A list of measurements in increasing order is 4, 5, 6, 8, 10 and x. If the median of these measurements is 6/7 times their arithmetic mean, what is the value of x? A. 16 B. 15 C. 14 D. 13 E. 12 Median of a set with even # of terms = Average of the middle two terms = \(\frac{(6+8)}{2} >\frac{14}{2} > 7\) Median is 7 ; Mean = \(\frac{(4+5+6+8+10+x)}{6}\) Given that Median = \(\frac{6}{7}\) of Mean Median =\(\frac{6}{7}* \frac{(4+5+6+8+10+x)}{6}\) \(7 = \frac{6}{7}* \frac{(4+5+6+8+10+x)}{6}\) \(7=\frac{6}{7} * \frac{(33+x)}{6}\) \(49=33+x\) \(x=4933\)\(x=16\) ANSWER IS A
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Re: A list of measurements in increasing order is 4, 5, 6, 8, 10 and x. If [#permalink]
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26 Sep 2017, 16:34
udaymathapati wrote: A list of measurements in increasing order is 4, 5, 6, 8, 10 and x. If the median of these measurements is 6/7 times their arithmetic mean, what is the value of x?
A. 16 B. 15 C. 14 D. 13 E. 12 We are given the following measurements in increasing order: 4, 5, 6, 8, 10, x Let’s first calculate the mean: average = sum/quantity avg = (4 + 5 + 6 + 8 + 10 + x)/6 avg = (33 + x)/6 We also know that the median of the set is (6 + 8)/2 = 14/2 = 7 Since the the median of these measurements is 6/7 times the arithmetic mean, we can create the following equation: (6/7)*[(33 + x)/6] = 7 6*(33 + x)/6 = 49 33 + x = 49 x = 16 Answer: A
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