<p>On page 587 (Practice Test #3, Section 2,) how do you do number 19? I just can't seem to figure it out. Is there some information missing or has my pathetically-small, non-math-oriented brain just shut down from overuse.
Thanks</p>
<p>ehh
just look at all the answer options
cross multiply in all the answer options so that there are no fractions
the one that doesnt match with the rest of the equations is the correct answer </p>
<p>:)</p>
<p>Thanks!
Whenever I attempt to do math, I can just feel my brain turn to cotton candy inside my head as I start muttering vacuous Hmmm s à la Jessica Simpson.</p>
<p>Another option is to just substitute.</p>
<p>So, make the first option true with a=1; f=2; b=2; c=4;</p>
<p>Then, use the same numbers on the rest. If it doesn’t make the next two true, then you know you’ve got your answer.</p>
<p>(Sorry to resurrect an old thread, but figured having this in here would be helpful for other people going through the blue book like me.)</p>