Monday Mail-Bag: Advice on Big Picture Issues That Impact GMAT Test Takers…This series of emails and PMs focuses on situations that many Test Takers face during their studies. The names of the original posters have been changed to protect their identities.
Strange Graphing Questions on the GMATHello Rich,
I wasn’t sure how to handle this graphing question. Any advice?
How many times does graph y = ax^2 + bx + c intersect the x-axis?
1) a > 0
2) c < 0
OA: C
I was also wondering if these types of questions are likely to be tested on the GMAT?
Filmore
Hi Filmore,
The concepts in this DS question are quite rare, but possible, on the GMAT. I wouldn't put too much time or energy into these sorts of graphing questions though, as you're not likely to see this on Test Day. That all having been said, there are some Number Properties behind this type of graphing:
1) A graph of a quadratic will be a "U" shape (either "open up" or "open down").
If the "a" variable is positive, then the graph opens "up"; if the "a" is negative, then the graph opens "down"; if the "a" is 0, then you have a line.
2) The graph of a quadratic will intersect the X-axis at 0, 1 or 2 points.
3) The y-intercept of this line (the "c" variable) is important because it anchors the graph at a point and then the graph either opens "up" or "down"
Fact 1: "a" is positive
This tells us that the graph opens "up", but we don't know where the y-intercept is:
If "c" is positive, then the answer is 0
If "c" is 0, then the answer is 1
If "c" is negative, then the answer is 2
Fact 1 is INSUFFICIENT
Fact 2: "c" is negative
This tells us the y-intercept is negative, but we don't know if the graph opens "up" or "down":
If "a" is positive, then the answer is 2
If "a" is 0, then the answer is 1
If "a" is negative, then the answer is 0
Fact 2 is SUFFICIENT
Combined, we know the "a" is positive (so the graph opens "up") and the "c" is negative (so the y-intercept is negative). This graph would have 2 intercepts.
Combined, SUFFICIENT
Final Answer: C
Which SC Rule to Tackle First…Dear Rich,
When dealing with the following SCs, what is the best rule to start with?
The plot of The Bostonians centers on the rivalry between Olive Chancellor, an active feminist, with her charming and cynical cousin, Basil Ransom, when they find themselves drawn to the same radiant young woman whose talent for public speaking has won her an ardent following.
(A) rivalry between Olive Chancellor, an active feminist, with her charming and cynical cousin, Basil Ransom
(B) rivals Olive Chancellor, an activist feminist, against her charming and cynical cousin, Basil Ransom
(C) rivalry that develops between Olive Chancellor, an active feminist, and Basil Ransom, her charming and cynical cousin
(D) developing rivalry between Olive Chancellor, an active feminist, with Basil Ransom, her charming and cynical cousin
(E) active feminist, Olive Chancellor, and the rivalry with her charming and cynical cousin Basil Ransom
Garfield
Hi Garfield,
You're going to find that the GMAT tests Parallelism rules repeatedly on Test Day, and in variety of ways. Here, we're dealing with "2-Part" Parallelism, which requires that the 2 parts be similar (and be presented in the same way). The parallelism might also use a "2-Part" phrase (such as either…or, neither…nor, between…and).
The way that the original prompt is written certainly hints that the phrase "between…and" will appear in the correct answer, but we won't know for sure until we run through the answers and consider the parallelism.
1) Between…and: Eliminate A (no "and"), and D (no "and")
2) Parallelism in general: Eliminate B (should be "on the rivals….Olive Chancellor AND….Basil Random) and E (should be "Olive Chancellor AND...Basil Ransom").
Final Answer: C
Too Much Study Can Lead to ‘Burnout’Dear Rich,
Thanks a lot for your inputs and suggestions so far. I am planning to give my GMAT within the next 2.5 months. or before that, I can't delay it further as other plans are also in queue. Since I’m not doing anything else right now, my plan is to study 8 hours every day (and on the weekend I can spend even more hours than that if needed). Do you have any advice about how I should spend my time?
Harrison
Hi Harrison,
It sounds like you've given yourself enough time to study, as 2.5 months is plenty. However, I’m concerned that you are likely to study too much during that time. As your studies progress, you might find it helpful to give yourself one day "off" per week - so that you can relax a bit (and do something other than study). While some Test Takers feel compelled to study every day, there is a long-term risk of "burn out" and it's best to try to plan proactively to keep that from happening. By extension, studying 8 hours a day (or more) is almost certainly too much as well.
You should do your studies in small ‘chunks’ – no more than 2 hours at a time (with the exception of your CATS, which will obviously take longer to complete). After 2 hours of study, you should take an hour ‘off’; if you want to do multiple 2-hour blocks during the day, then that’s fine, but I would never ask anyone to study more than 6 hours in a day, so you should keep that in mind when planning out your schedule.
GMAT assassins aren't born, they're made,
Rich
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