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mmeyer5
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Fractions, Decimals, & Percents page 83, number 14 solution

by mmeyer5 Tue Aug 06, 2013 4:10 pm

Hi, so I'm studying this book and I'm wondering if this solution is a typo. This is a Quantitative Comparison question, however in the solution you have to do some decimal division for Quantity A, but the solution has you perform multiplication on Quantity B, which is really bewildering to me as Quantity A and B should be mutually exclusive and there is no need to perform the same action on both quantities. If this is a typo, no problem please just let me know the correct answer
tommywallach
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Re: Fractions, Decimals, & Percents page 83, number 14 solution

by tommywallach Tue Aug 06, 2013 11:09 pm

Hey mmeyer,

Actually, this is an incredibly important technique to learn in order to work on QC (our book on QC explains it in more detail).

Basically, you can treat the two columns as if they were a giant inequality with a question mark:

Quantity A Quantity B

50/3 > 49/3 ?

In this case, we could multiply both A and B by 3

50 > 49 ?

And now we have a more obvious answer.

Make sense?

-t
mmeyer5
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Re: Fractions, Decimals, & Percents page 83, number 14 solution

by mmeyer5 Wed Aug 07, 2013 5:44 pm

Wow, thank you Tommy. That helps a lot!
tommywallach
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Re: Fractions, Decimals, & Percents page 83, number 14 solution

by tommywallach Tue Aug 13, 2013 8:49 am

Glad to help! : )

-t