Median Values Question

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Median Values Question

by mihai9 » Thu Nov 09, 2017 1:33 pm
15 * j * 6 * k, is the median greater or equal to 10?
1: j is even
2: jk is a multiple of 7

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by Matt@VeritasPrep » Thu Nov 09, 2017 7:04 pm
It's impossible to tell what the prompt is giving us. 15 * j * 6 * k is an expression, not a set, so we don't know the set whose median we seek or how to do anything with 90jk.

If the prompt is asking
Is the median of the set {6, 15, j, k} greater than 10?
that's a different story, but I'd need to know more before answering.

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by mihai9 » Thu Nov 09, 2017 9:14 pm
Matt@VeritasPrep wrote:It's impossible to tell what the prompt is giving us. 15 * j * 6 * k is an expression, not a set, so we don't know the set whose median we seek or how to do anything with 90jk.

If the prompt is asking
Is the median of the set {6, 15, j, k} greater than 10?
that's a different story, but I'd need to know more before answering.
Thanks Matt sorry it's my keyboard problem, your quote is correct

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by mihai9 » Thu Nov 09, 2017 9:14 pm
Matt@VeritasPrep wrote:It's impossible to tell what the prompt is giving us. 15 * j * 6 * k is an expression, not a set, so we don't know the set whose median we seek or how to do anything with 90jk.

If the prompt is asking
Is the median of the set {6, 15, j, k} greater than 10?
that's a different story, but I'd need to know more before answering.
Thanks Matt sorry it's my keyboard problem, your quote is correct

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by Matt@VeritasPrep » Fri Nov 10, 2017 1:29 pm
OK, great!

{6, 15, j, k} can have a median less than 10 only if 15 is the largest number in the set. (If it isn't the largest, then our set would be {j, 6, 15, k} or {6, j, 15, k}, in which case the median is at least 10.5)

From here, I'd try a few sets. We could have j = 2, k = 7, which gives us {2, 6, 7, 15} and a median of 6.5, but we could also have j = 20, k = 70, which gives us {6, 15, 20, 70} and a median of 17.5.