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danc
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QC book, chapter 3 set, #8

by danc Tue Dec 02, 2014 6:40 pm

In a question like this, to evaluate A and B it is ok to assume x is a different number in each quantity? When looking at the minimum possible values for the quantities, x does not have to be the same number in A as it is in B?
tommywallach
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Re: QC book, chapter 3 set, #8

by tommywallach Tue Dec 02, 2014 9:48 pm

Be careful. If you're checking values for x, you DO have to use the same value for each column. You can test multiple values, but always the same value in each column. Otherwise, x is no longer x, but y (so to speak).

-t
danc
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Re: QC book, chapter 3 set, #8

by danc Wed Dec 03, 2014 2:14 am

Ok, but for this question, as we're testing values, if the value for the expression in A is minimized by one value for x and the value for the expression in B is minimized by a different value for x, those are the values we "go with" when picking an answer (even though they are different) because we are looking for the minimum possible values for A and B not a comparison of the values of A and B when utilizing the same value for x. That seems to be what the answer explanation is saying, just wanted to confirm that.
tommywallach
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Re: QC book, chapter 3 set, #8

by tommywallach Sat Dec 06, 2014 4:20 pm

Yes! Absolutely.

-t