800score.com overlapping set problem

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fskilnik@GMATH: GMAT Instructor; Posts: 1449; Joined: Sat Oct 09, 2010 2:16 pm; Thanked: 59 times; Followed by:33 members

by fskilnik@GMATH » Mon Feb 28, 2011 4:47 am

lunarpower wrote:
My suggestion: run away from "picking/plugging numbers", "back-solving" or other "hocus-pocus smart techniques" because this sort of thing will be "blocked" by the examiners when you start to go really well in your ADAPTIVE exam.
no offense, but, this is probably the wrong-est thing i've ever seen written on this forum.

in any case, "running away" from any method that has a decent success rate is a rather silly idea: because of the unusual and unconventional nature of the problems, the ideal goal is to accumulate AS MANY METHODS AS POSSIBLE for solving them.
if a problem can be solved by "textbook methods" AND by, say, backsolving, then you should learn both methods! this way, if the first thing you try on test day doesn't work, you have ... something else to try.

put another way -- if i only have 1 way to approach a problem, while you have 3 ways to approach that problem (including my 1 way!), then i lose and you win.

Hi there, Ron (and others).

Let me put my opinion in a more clear way: I believe students should use problems to deepen their understanding of the content involved in the GMAT, simply because "all the market" teaches the "smart stuff" and the test itself is adaptive, therefore while it will be possible to "avoid" solving the problem, many candidates will be able to get the right answer, but when the examiner "blocks" it (as shown below), the MAJORITY of test-takers will be feeling "orphans"...

Example: what is the value of x such that .... ?

(A) 20
(B) 30
etc

the student may try 20, 30, till he/she gets the right answer.

Example: If x is such that... , if x = ab, where a and b are positive digits, what is the value of a+b ?

(A) 9
(B) 10
(C) 11
(D) 12
etc

Now the student should come to the (say) answer x = 57 to be able to click 5+7 = 12 (D) answer...

More than that, my (almost 11 years experience) shows me that my students with greater QUANTITATIVE MATURITY are the ones who systematically get the better marks. In my experience, thatÂ´s a FACT. In this sense, I believe understanding and developing proper math tools is the best way to increase the studentÂ´s quantitative maturity, but of course this is just my experience and it is biased from the fact that I see the GMAT exam through my own eyes, of course.

In terms of having just 1 method versus more than one, you are right, sure, but I believe we are talking about FOCUS on methods, giving priority in some of them, and not in others, during the studentÂ´s study. People who teach "smart stuff" are, in general, giving no emphasis in the math itself and, in my opinion, they are wrong when doing that. I do not put emphasis in "smart stuff" because, in my experience, students come naturally to that. My role is exactly to put the "SECOND" way to work, and to show them that this "MATH approach" may put them where the "smart-stuff" couldnÂ´t, in terms of math maturity and, as a consequence, a higher GMAT score.

Again: itÂ´s just a matter of opinion and I respect your disagreement.

Regards,
Fabio.

Fabio Skilnik :: GMATH method creator ( Math for the GMAT)
English-speakers :: https://www.gmath.net
Portuguese-speakers :: https://www.gmath.com.br

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lunarpower: GMAT Instructor; Posts: 3380; Joined: Mon Mar 03, 2008 1:20 am; Thanked: 2256 times; Followed by:1535 members; GMAT Score:800

by lunarpower » Mon Feb 28, 2011 5:24 am

fskilnik wrote:when the examiner "blocks" it (as shown below), the MAJORITY of test-takers will be feeling "orphans"...

yes, of course there will be problems on which the backup methods don't work; that's why they're backup methods. i.e., they are things to try if the student doesn't understand how to solve the problem in the traditional way!
in this sense, this argument isn't really an argument at all -- i'm not advocating that we replace textbook approaches with backup methods, but, rather, that we supplement textbook approaches with backup methods.

moreover, there are very few questions that incorporate these kinds of intentional "blocks" -- because that's not what this test is about.

real, authentic GMAT problems are usually designed so that they can be solved by a variety of methods, including plugging methods!
this test isn't designed to measure students' aptitude with obscure, advanced mathematical approaches; hence why the material of the test doesn't go beyond what a student would learn in high school algebra and geometry. (if the test were truly meant to be a measure of "quantitative maturity", then it would go a lot further than that.)
instead, if you look at enough official problems, it becomes manifestly clear that the test writers' #1 priority is exactly the opposite of "blocking" these methods; their priority is to write problems that can be solved by "backup methods" quite often, so that the test can fulfill its purpose as a reasoning test (i.e., specifically not as a test of raw quantitative achievement).

in fact, if you look at the last 40-50 PS problems in OG12 -- a sample that fairly represents higher-difficulty problems -- you can solve, or at least narrow, 60-70% of them using only the following three methods:
* estimate the answer
* plug in your own value ("VIC" approach in mgmat books)
* work backward from the answer choices

60-70%!!!
if this number were even 20-30% these methods would still be of crucial importance -- but it's over half of the problems.

Example: If x is such that... , if x = ab, where a and b are positive digits, what is the value of a+b ?

(A) 9
(B) 10
(C) 11
(D) 12
etc

Now the student should come to the (say) answer x = 57 to be able to click 5+7 = 12 (D) answer...

this sort of thing is *very* rare on PS problems. very rare indeed.
it's somewhat common on DS problems, but the plugging methods that work on those problems are different (and are, in fact, compatible with this sort of question prompt).

More than that, my (almost 11 years experience) shows me that my students with greater QUANTITATIVE MATURITY are the ones who systematically get the better marks. In my experience, thatÂ´s a FACT.

well, obviously, yes, of course there will be a positive correlation between "quantitative maturity" and gmat quant score -- i'm sure you realized this in your first 11 hours of teaching this test.

however, this fact also has nothing at all to do with whether those quantitative scores are also impacted by a student's learning these backup methods.
in fact, it seems you're making an assumption that only one factor can have a causal effect on quant scores! i.e., the apparent line of reasoning here is "quant scores are positively correlated with raw 'quantitative maturity'; therefore, they must *not* be correlated with any other factor."
hmmmm

In this sense, I believe understanding and developing proper math tools is the best way to increase the studentÂ´s quantitative maturity, but of course this is just my experience and it is biased from the fact that I see the GMAT exam through my own eyes, of course.
In terms of having just 1 method versus more than one, you are right, sure, but I believe we are talking about FOCUS on methods, giving priority in some of them, and not in others, during the studentÂ´s study. People who teach "smart stuff" are, in general, giving no emphasis in the math itself and, in my opinion, they are wrong when doing that. I do not put emphasis in "smart stuff" because, in my experience, students come naturally to that. My role is exactly to put the "SECOND" way to work, and to show them that this "MATH approach" may put them where the "smart-stuff" couldnÂ´t, in terms of math maturity and, as a consequence, a higher GMAT score.

right. but there are 2 further factors that need to be considered here:

1) you don't want students to overextend themselves: the solution you've posted in this thread is mathematically beautiful, but it's not the kind of thing that students should study -- it's way too complicated and advanced to be analogous to any problem that a student will actually see on this test. (you admitted yourself that it took you far longer than 2 min. -- if that's the case, then there is a real problem; it really shouldn't take an instructor more than 1-1.5 minutes to solve *any* quant problem.)
i.e., i am afraid that students who seen that approach are going to feel validated in spending 3, 4, even 5 minutes the next time they see a three-set overlapping set problem.
so, yeah, teaching "textbook math" is good, but as instructors we've got to be vigilant about rejecting third-party problems that are obviously too hard for the real test. i.e., the problem in this thread is the sort of problem that simply shouldn't be discussed at all in a gmat forum, lest it have a pernicious effect on students' time management and perception of the test.

2) total length of study program: this is the real problem with any approach that's purely based on textbook type math -- it takes a really, really, REALLY long time to accomplish any significant improvement. for instance, the kind of approach that's presented in this thread would probably take an hour or two of studying, plus practice, for most students -- and it only works on a very specific type of problem that doesn't even show up on most gmat administrations!
the same is true for the vast majority of other orthodox mathematical methods -- each specific topic requires several hours of study and practice, and there are probably at least a hundred specific topics in the quant section. so we're talking a looooooooooong time here.
by contrast, the backup methods (plugging, etc) only take a couple of weeks to learn and master -- and, as noted above, they are effective on a majority of the problem-solving questions! in terms of return on a student's time investment, there is no question that these methods are the most effective.

i've actually seen students improve their Quant score by 10+ points in just a couple of weeks, just by studying these backup methods. in fact, a recent tutoring student of mine went from Q29 to Q41 in two weeks by studying absolutely nothing but backup methods -- an improvement that, i daresay, is absolutely impossible to match by studying textbook methods.

Ron has been teaching various standardized tests for 20 years.

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lunarpower: GMAT Instructor; Posts: 3380; Joined: Mon Mar 03, 2008 1:20 am; Thanked: 2256 times; Followed by:1535 members; GMAT Score:800

by lunarpower » Mon Feb 28, 2011 5:32 am

I do not put emphasis in "smart stuff" because, in my experience, students come naturally to that.

i found this statement especially interesting -- is this really true? the majority of your students actually come up with the backup methods by themselves?
if so, then your students are, to say the least, incredibly different from mine; the vast majority of my students would never even think of using non-textbook methods to solve a problem, without considerable prodding.
the same is also true of many (if not most) posters on this forum -- way too much emphasis on rules, memorization, and protocol, and nowhere near enough emphasis on intuitive and strategic methods.

in short -- if these methods really "come naturally" to your students, then your students are a very small (and blessed) minority. by contrast, the majority of gmat aspirants know basically all of the mathematical facts that they need to know, but strategy is where they fall short.

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kevincanspain: GMAT Instructor; Posts: 613; Joined: Thu Mar 22, 2007 6:17 am; Location: madrid; Thanked: 171 times; Followed by:64 members; GMAT Score:790

by kevincanspain » Mon Feb 28, 2011 6:24 am

HPengineer wrote:In a 100 unit dormitory building, 75 dorm rooms have at least one DVD player, 80 have at least one cell phone and 55 have at least one MP3 player. Every dorm has at least one of these three devices. If x and y are respectively the greatest and lowest possible number of dorms that have all three of these devices then x-y is:

A.65
B.) 55
C.) 45
D.) 10
E.) 0

I having trouble setting up a table to approach this... so i drew venn diagram instead.. i get close to the answer but not quite...

M = set of dorm rooms with MP3
C = ... cell phone
D= ... DVD player

To find the value of x, it could be that M is a subset of D, which is a subset of C. In that case 55 would have all three : x =55

To find the value of y, minimize the number of rooms in both M and C . Suppose that the 45 not in M are separate from the 20 not in C. In that case 100-45-20= 35 rooms would have both MP3 and cellphone. Since 25 rooms are not in D, at least 10 of these 35 rooms would be in D. y= 10

Kevin Armstrong
GMAT Instructor
Gmatclasses
Madrid

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kevincanspain: GMAT Instructor; Posts: 613; Joined: Thu Mar 22, 2007 6:17 am; Location: madrid; Thanked: 171 times; Followed by:64 members; GMAT Score:790

by kevincanspain » Mon Feb 28, 2011 6:34 am

I agree with Ron. Math wizards may scoff at these 'non-math' solutions, but the vast majority of my students really appreciate seeing them, even the engineers. It's not our job to turn students into mathematicians but rather to help them maximize their scores. I am quite good at math (average GMAT quant score 50.75), but for every question I face every time I do the GMAT, I at least consider whether a non-math approach would be more efficient.

In the question at hand, it is quite easy to find x and to realize that y should be much less than x. Even someone who could not do the work should realize that the answer is D. As is often the case, the best test takers often use a little math and the answer choices themselves to get the question right.

Kevin Armstrong
GMAT Instructor
Gmatclasses
Madrid

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fskilnik@GMATH: GMAT Instructor; Posts: 1449; Joined: Sat Oct 09, 2010 2:16 pm; Thanked: 59 times; Followed by:33 members

by fskilnik@GMATH » Mon Feb 28, 2011 8:09 am

lunarpower wrote:
fskilnik wrote:that's why they're backup methods. i.e., they are things to try if the student doesn't understand how to solve the problem in the traditional way!

If a student is studying for the GMAT and doesnÂ´t understand all to solve a problem in a MATH way (not necessarily traditional, not necessarily explained in the usual textbooks), I believe he/she should learn the content, not avoid it. I mean WHILE STUDYING for the GMAT... thatÂ´s different from DOING THE REAL THING.

lunarpower wrote: i'm not advocating that we replace textbook approaches with backup methods, but, rather, that we supplement textbook approaches with backup methods.

IÂ´m advocating to use (textbook or not) MATH approaches, as a strong tool. Not as a substitute for avoiding the knowledge involved in the question at hand.

lunarpower wrote: moreover, there are very few questions that incorporate these kinds of intentional "blocks" -- because that's not what this test is about.

I will not discuss "there are few" (some of my 49-50 quant scores students would disagree) and will not discuss what the test is about. I guess neither one of us could do that. The GMAT is a great "math sniffer" IMHO, but thatÂ´s only MHO, please accept that.

lunarpower wrote: this test isn't designed to measure students' aptitude with obscure, advanced mathematical approaches; hence why the material of the test doesn't go beyond what a student would learn in high school algebra and geometry. (if the test were truly meant to be a measure of "quantitative maturity", then it would go a lot further than that.

You are deeply wrong. The fact that the Math involved is almost trivial allows them to ask it deeply. In other words, if the Math would be too advanced, people could complain that they donÂ´t need to know that to be a (say) MBA... the fact that the GMAT tests only basic Math allows them to ask (say) a lawyer to be able to think with maturity on subjects he/she ALSO LEARNED before he/she went to the University. I tell my students that BECAUSE itÂ´s easy Math, itÂ´s hardly asked. Because itÂ´s trivial subjects, they are allowed to ask peculiar details about them!

lunarpower wrote: instead, if you look at enough official problems, it becomes manifestly clear that the test writers' #1 priority is exactly the opposite of "blocking" these methods; their priority is to write problems that can be solved by "backup methods" quite often, so that the test can fulfill its purpose as a reasoning test (i.e., specifically not as a test of raw quantitative achievement).

Official exercises are FAR TOO EASY as compared to the real GMAT ones IF THE STUDENT is a TOP one! Therefore every deduction based on official (published) ones is flawed.

lunarpower wrote: in fact, if you look at the last 40-50 PS problems in OG12 -- a sample that fairly represents higher-difficulty problems

They are not. Higher-Difficulty problems the candidate WILL find in the real exam IF HE/SHE "DESERVES". My experience shows me that with 100% objectivity.

lunarpower wrote: this sort of thing is *very* rare on PS problems. very rare indeed.

Sorry. It may be rare in your experience, but I am talking about what APPEARS on the test, and I am really not that interested in "averages". I want my students to succeed, and I mean to have an outstanding performance, I am not here to cover (say) what he/she needs to know to get (say) 80% in Math. I know most methods are oriented to the average-student. Mine is not. I try to convince my students to learn my approach. They do. They get very high-marks.

lunarpower wrote: in fact, it seems you're making an assumption that only one factor can have a causal effect on quant scores! i.e., the apparent line of reasoning here is "quant scores are positively correlated with raw 'quantitative maturity'; therefore, they must *not* be correlated with any other factor."

Please, Ron, do not put words in my mouth. I tell you what I believe works, you have the right to think differently. Give me the same right, shall you?

lunarpower wrote: 1) you don't want students to overextend themselves: the solution you've posted in this thread is mathematically beautiful, but it's not the kind of thing that students should study -- it's way too complicated and advanced to be analogous to any problem that a student will actually see on this test. (you admitted yourself that it took you far longer than 2 min. -- if that's the case, then there is a real problem; it really shouldn't take an instructor more than 1-1.5 minutes to solve *any* quant problem.)
i.e., i am afraid that students who seen that approach are going to feel validated in spending 3, 4, even 5 minutes the next time they see a three-set overlapping set problem.

As I explained, after I took more-than-2-minutes I understood what would take to solve the same thing in say approx. 2min, thatÂ´s all. The fact is that, as you said, this is really hard-above-average stuff and, even being so, if I am being able to show my students how to do it in say 2.5 min during the test AFTER LEARNING HOW TO I guess itÂ´s 100% kosher. In other words, we learn from our mistakes and we learn by getting structures where we didnÂ´t have one prior to a specific problem. My students may or may not wish to learn my solution (they CAN use trials etc) but I want to give them this option. What the student should or should not study is a matter of opinion and method. I respect yours.[/quote]

lunarpower wrote: so, yeah, teaching "textbook math" is good, but as instructors we've got to be vigilant about rejecting third-party problems that are obviously too hard for the real test.

I agree but THIS specific problem I solved to them (and here) BECAUSE a student of mine, AFTER THE REAL TEST, discussed with me a problem similar to that that he was NOT capable of doing. So, in a way, this IS GMAT stuff, although really high-level.

lunarpower wrote: 2) total length of study program: this is the real problem with any approach that's purely based on textbook type math -- it takes a really, really, REALLY long time to accomplish any significant improvement.

Believe me, itÂ´s not that long... well, it takes approximately 15 lessons of 1h each, and approx. 70 problems/class to absorb it... then my students need to do (say) 10-20 mocks to be sure he/she is able to USE the techniques with dinamism and competence. Not all of them absorb (say) 80% of what I teach, but the ones wo get (say) 70% or more have really high marks. ThatÂ´s my experience.

lunarpower wrote: by contrast, the backup methods (plugging, etc) only take a couple of weeks to learn and master -- and, as noted above, they are effective on a majority of the problem-solving questions! in terms of return on a student's time investment, there is no question that these methods are the most effective.

They are much quicker, for sure. ItÂ´s a matter of choice. If a student has (say) 2 weeks to prepare for his test, I suggest he goes to other (competent) teachers here in Brazil that are "masters of smart moves". Really. No prejudice here.

I guess we could stop here. I really believe both of us made ourselves clear.

Best Regards,
FÃ¡bio.

Fabio Skilnik :: GMATH method creator ( Math for the GMAT)
English-speakers :: https://www.gmath.net
Portuguese-speakers :: https://www.gmath.com.br

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fskilnik@GMATH: GMAT Instructor; Posts: 1449; Joined: Sat Oct 09, 2010 2:16 pm; Thanked: 59 times; Followed by:33 members

by fskilnik@GMATH » Mon Feb 28, 2011 8:33 am

kevincanspain wrote:I agree with Ron. Math wizards may scoff at these 'non-math' solutions, but the vast majority of my students really appreciate seeing them, even the engineers. It's not our job to turn students into mathematicians but rather to help them maximize their scores.

I am just saying that in my view the "Math approach" should have more development during a GMAT high-level prep than it usual does. The "smart stuff approach" is already well-established. Sure it is. Mainly (in my opinion) because itÂ´s the easier and quicker approach for the average question. Just that. But again, thatÂ´s my opinion.

I teach engineers, lawyers, journalists, etc. ItÂ´s not a matter of "turning them into mathematicians" (they donÂ´t want that, nor I have the merit to do that, nor the will... letÂ´s not over-simplify things)... but (in my experience) they get MUCH better in few months because of this "technical approach".

Regards,
Fabio.

Fabio Skilnik :: GMATH method creator ( Math for the GMAT)
English-speakers :: https://www.gmath.net
Portuguese-speakers :: https://www.gmath.com.br

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fskilnik@GMATH: GMAT Instructor; Posts: 1449; Joined: Sat Oct 09, 2010 2:16 pm; Thanked: 59 times; Followed by:33 members

by fskilnik@GMATH » Mon Feb 28, 2011 8:51 am

lunarpower wrote:is this really true? the majority of your students actually come up with the backup methods by themselves? If so, then your students are, to say the least, incredibly different from mine; the vast majority of my students would never even think of using non-textbook methods to solve a problem, without considerable prodding.

Perhaps the difference is that you get students that know nothing about the GMAT in the first place. Most of my students have already studied by themselves (through books or online courses) for some weeks, or even at other prep schools for months. Some of them come here with a low score, wishing to improve it substancially.

lunarpower wrote: the same is also true of many (if not most) posters on this forum -- way too much emphasis on rules, memorization, and protocol, and nowhere near enough emphasis on intuitive and strategic methods.

Uau... we disagree on that, too. Some experts use textbook without strategic moves, others are proud to avoid textbooks whenever possible but out-of-the-box *technical* solutions/insights are rare, in my opinion.

Well, I donÂ´t believe:

01) technical way = protocol/textbook way (necessarily).
02) intuitive and strategic methods <> technical ones (necessarily).

I guess some of my posts have already shown how math and strategy may (SHOULD) come together, by the way.

(Please feel free to read some of my BTG posts and criticize them, on this matter. I would really thank you for that.)

lunarpower wrote:the majority of gmat aspirants know basically all of the mathematical facts that they need to know, but strategy is where they fall short.

Sorry, I disagree. My students do NOT remember that

01) "an inscribed triangle is right if and only if one of its sides is a diameter of the circle that circumscribes it"
02) Two non-horizontal nor vertical lines (in a plane) are perpendicular if and only if the product of their slopes is -1
03) Prob(A and B) = Prob(A) * Prob(B) if and only if events A and B are independent

but even after I tell them about this, they need to learn the "working knowledge", that is, the ability to put this info "to work" by specific strategic technical methods.

Fabio Skilnik :: GMATH method creator ( Math for the GMAT)
English-speakers :: https://www.gmath.net
Portuguese-speakers :: https://www.gmath.com.br

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DanaJ: Site Admin; Posts: 2567; Joined: Thu Jan 01, 2009 10:05 am; Thanked: 712 times; Followed by:550 members; GMAT Score:770

by DanaJ » Mon Feb 28, 2011 9:46 am

Hi everyone,

Thank you very much for your contributions up to now. I know you are all active members of our community and I appreciate that. On the other hand though, I feel like this discussion is going a bit beyond the scope of the original message. I'm no more than your average test taker and I personally feel like this discussion is a bit too much/too philosophical.

Thanks everyone,

Dana

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Night reader: Legendary Member; Posts: 1337; Joined: Sat Dec 27, 2008 6:29 pm; Thanked: 127 times; Followed by:10 members

by Night reader » Mon Feb 28, 2011 10:02 am

Hi Ron and Kevin, I think the way Fabio is trying to teach GMAT's Quantitative part is standing VERY close to the exam in its present "state of affairs". Although many GMAT prep books keep on telling us that GMAT"s Quantitative part is testing only our high school (college) math wiz - that's just not true. I remember even Geva Stern has once suggested that the Quant is just high school math...

My exam experience from February 17 (that's just as recent and fresh as might be the donuts baked at the corner

) suggested GMAT's Quant is the test of our quantitative abilities with wide meaning plethoras. One must prepare himself/herself for knowing nothing about the test's content and should solve questions analytically rather than mechanically - and I reject the backwords, plug-ins, backups and other blas (sorry) as some useful solution tricks. These are just as detrimental as the ones standing on the peak of the mechanical approach to GMAT's Quant - these may see one off the corner in exam by being totally out-beaten...

For scoring high in GMAT's Quant it is required to prepare analytically for the exam. One needs to turn the creativity ON. This feature (creativity) is just unavoided by people with tech backgrounds - that's they were academically raised this way... to think creatively and score high on GMAT's Quant

. A person can study days and nights all his math prep.books and still will lag behind some other test-takers with the tech. backgrounds who may be prepared for a week or two to take GMAT exam.

Cutting this short, and yet trying to share another observation I have made from my GMAT preparation - CATs at home and CATs at the test center are two different things. When I am home - I feel so relaxed and high-moody to become creative and start analyzing the complex questions ... but hell outside of my home I just keep walking the road, I have walked all my life -- no one can turn me from my usual road

that's just a psychological barrier that needs to be broken by myself to become creative and maintain analytical approach to replace the mechanical -"I walk my usual way with the head down to my road, and nobody can disturb me from my road, heh "

yes, and thank you for the interesting dispute here - one stemmed from a set question, I guess

My knowledge frontiers came to evolve the GMATPill's methods - the credited study means to boost the Verbal competence. I really like their videos, especially for RC, CR and SC. You do check their study methods at https://www.gmatpill.com

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Night reader: Legendary Member; Posts: 1337; Joined: Sat Dec 27, 2008 6:29 pm; Thanked: 127 times; Followed by:10 members

by Night reader » Mon Feb 28, 2011 10:10 am

Dana, that's quite useful discussion going over math forum - sometimes people need to raise their heads and think/ask "what they do and why they do?"

DanaJ wrote:Hi everyone,

Thank you very much for your contributions up to now. I know you are all active members of our community and I appreciate that. On the other hand though, I feel like this discussion is going a bit beyond the scope of the original message. I'm no more than your average test taker and I personally feel like this discussion is a bit too much/too philosophical.

Thanks everyone,

Dana

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fskilnik@GMATH: GMAT Instructor; Posts: 1449; Joined: Sat Oct 09, 2010 2:16 pm; Thanked: 59 times; Followed by:33 members

by fskilnik@GMATH » Mon Feb 28, 2011 11:08 am

DanaJ wrote:Hi everyone,

Thank you very much for your contributions up to now. I know you are all active members of our community and I appreciate that. On the other hand though, I feel like this discussion is going a bit beyond the scope of the original message. I'm no more than your average test taker and I personally feel like this discussion is a bit too much/too philosophical.

Thanks everyone,

Dana

I agree, Dana, and I must apologise for that. IÂ´ll not go into this matter further, not now nor in the future.

I hope no one took my different views as an offense, because it was not my intention and also because itÂ´s for me a pleasure (really) to be able to see (daily!) other approaches/views "working". I respect all that and I feel very welcomed here, and for this I am really thankful.

Regards,
Fabio.

Fabio Skilnik :: GMATH method creator ( Math for the GMAT)
English-speakers :: https://www.gmath.net
Portuguese-speakers :: https://www.gmath.com.br

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lunarpower: GMAT Instructor; Posts: 3380; Joined: Mon Mar 03, 2008 1:20 am; Thanked: 2256 times; Followed by:1535 members; GMAT Score:800

by lunarpower » Mon Feb 28, 2011 6:00 pm

Night reader wrote:I reject the backwords, plug-ins, backups and other blas (sorry) as some useful solution tricks.

the experiences of my students cited above speak for themselves -- i've had several students make sizable improvements in a very short time, including one student's progress from q29 to q41 in two weeks, by studying nothing but backup methods.

moreover, there are many official questions that are very clearly designed with backup methods in mind. for instance, look at problem #164 in the green 2nd edition quantitative supplement -- it's obvious that the test writers had "work backward" (which reduces the problem to 3rd grade arithmetic) in mind while writing this problem, even though the answer key contains some craziness.

also -- your other post indicated that your quant score had fallen by 10-15 points from your previous administration. this seems to indicate that your approaches to the quant section aren't working, and that you could use some additional perspective(s) -- including other solution methods that you're currently rejecting.

One needs to turn the creativity ON.

how do you reconcile "turn the creativity on" with "i reject backup methods"? that doesn't make sense -- the backup methods are creative solutions.

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lunarpower: GMAT Instructor; Posts: 3380; Joined: Mon Mar 03, 2008 1:20 am; Thanked: 2256 times; Followed by:1535 members; GMAT Score:800

by lunarpower » Mon Feb 28, 2011 6:06 pm

Although many GMAT prep books keep on telling us that GMAT"s Quantitative part is testing only our high school (college) math wiz - that's just not true.

NR, can you name any topics tested on the GMAT that aren't introduced by the end of a high-school algebra and geometry course?
if so, i'd be extremely interested -- because i've never seen a single one.

the content on the gmat is specifically restricted to material from high-school algebra, geometry, and earlier courses, because the purpose of the exam is to test quantitative reasoning, not quantitative knowledge or achievement.
even topics that are normally studied later in the high school curriculum -- such as trigonometry and single-variable calculus -- are omitted from the test, for the same reason.

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