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maria08
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range of a set

by maria08 Mon Dec 02, 2013 5:13 pm

Hi
A set of consecutive integers contain -4 and 6. However, -6 and 9 are not in the set.

Column A
The range of the set

Column B
13

I think the solution is D as the exact # of integers is not specified. Some help would be needed.
thanks :)
mihaela.taranu22
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Re: range of a set

by mihaela.taranu22 Thu Dec 05, 2013 5:45 am

I think you are right. The range can be 13 (the maximum as I can see) or can be lesser.
Then, yes, D seems to be the answer.
tommywallach
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Re: range of a set

by tommywallach Thu Dec 05, 2013 12:16 pm

Hey Maria,

Hmm. Well, your explanation makes me worry you don't quite understand QC. Maybe you're just being a little lazy on the explanation, but in the future, try to go a little further.

The answer is not (D) because the range isn't specified. It's (D) because the range that IS specified could be either EQUAL to 13, or LESS than 13.

The biggest the range could be is from -5 to 8, which would be a range of 13. This means the two columns COULD be equal, eliminating answer choices (A) and (B). From there, the range could be from -4 to 6, which would be a range of 10, meaning column A would be smaller than Column B, so the answer is (D).

To be clear, if the question were worded slightly differently, the answer would not be (D).

Question: A set of consecutive integers contain -4 and 6. However, -5 and 9 are not in the set.

This question would not be (D)!

-t
maria08
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Re: range of a set

by maria08 Tue Dec 17, 2013 8:31 am

I think I expressed myself quite poorly, but yes, my reasoning was similar to yours. cheers!
tommywallach
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Re: range of a set

by tommywallach Fri Dec 20, 2013 1:33 am

Cool!

-t