a list of measurements in increasing order is 4,5,6,8,10, x if the medium of these measurements is 6/7 times their arithmetic mean . what is x?
ans 16
please explain
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I remember this question. The answer choices, i think, were all greater than 10.
Hence x cannot be the median.
Hence the median is ( 6+8 )/2 = 7
Now, 7 = 6/7 [(4+5+6+8+10+x)/6]
Solving the above equation, you get x = 16
Hence x cannot be the median.
Hence the median is ( 6+8 )/2 = 7
Now, 7 = 6/7 [(4+5+6+8+10+x)/6]
Solving the above equation, you get x = 16
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Cybermusings
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median of the list = 6+8/2 = 7
Median = 6/7 times the arithmetic mean
7 = 6/7 * Mean
Thus Mean = 7*7/6 = 49/6
49/6 = 4 + 5 + 6 + 8 + 10 + x / 6
x = 49 - 33 = 16
Median = 6/7 times the arithmetic mean
7 = 6/7 * Mean
Thus Mean = 7*7/6 = 49/6
49/6 = 4 + 5 + 6 + 8 + 10 + x / 6
x = 49 - 33 = 16
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Jeff@TargetTestPrep
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We see that the median is (6 + 8)/2 = 7. Thus we have:yvonne12 wrote:a list of measurements in increasing order is 4,5,6,8,10, x if the medium of these measurements is 6/7 times their arithmetic mean . what is x?
(6/7)(4 + 5 + 6 + 8 + 10 + x)/6 = 7
(4 + 5 + 6 + 8 + 10 + x)/7 = 7
33 + x = 49
x = 16
Answer: 16
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