Good afternoon, good evening, good night, good morning depending on where you are in the world. This is Dr. Ferdinand. Uh this is a gold standard gamset webinar in which we are going to look at a handful of very challenging practice questions for the sciences and uh I hope that um the the lessons that you learn um by looking at these questions is you're you're going to discover is that once you understand it on once you see the key to the solution then it becomes easy and u I'm hoping that uh once you're able to do that then you will understand that uh there are many questions like this on the real exam that um are types of puzzles and in other words uh you know although we will be completing a unit that would be traditionally called organic chemistry uh another one which would be traditional ally called biology, another one which is physics. Uh the truth is that um uh these units have very little to do with those topics and they end up just being types of puzzles and um and so and this is reflected with the real exam as well. One of these puzzles, by the way, is going to be a mathematical matrix. And uh because you will be solving that uh in the unit that we will be doing uh it's going to make it so easy for you when you complete Acer's latest practice test which is their online practice test which they released real past recent uh GAMSAT questions from a real past exam uh recent past exam And in that exam there's a mathematical matrix. So once we do it together you will understand how that's solved and then uh either you've already completed Acer's uh mock exam the online mock exam which is their most recent material or you um hopefully will be completing it in the next few days and then you will laugh at Acer. you will mock them um because you will already know the key to the solution. Okay. Now um of course some of you know um I'm Dr. Ferdin. the author of the gold standard gamat books uh master series books and I also put uh on YouTube for free the stepbystep work solutions to all of the Acers um ebooks. So those are the five ebooks 440 multiple choice questions and so uh you can go on YouTube and you will be able to find that. Now today uh we'll be completing three units. Uh basically um you're going to uh we're going to complete them timed. You know the the new timing for uh the exam um as of the last two years is uh 2 minutes per question for uh the sciences section, 1.5 minutes per question for the humanities section. So you'll be getting two minutes uh per question uh to solve the six questions. So you'll get 12 minutes to solve the questions. Um and then uh you will be able to uh click to see the work solutions. Um as far as I know, Gold Standard is the only company that has a fulllength mock exam for free. So later um after this uh webinar you can complete the humanity section and you can complete the other sciences questions uh in the exam um if you uh if that interests you. And of course, I think that you should have already completed Acers's uh practice materials or that you uh will be completing them in the next week and then you can go through the work solutions that I put on uh YouTube. Uh I know that some of you have uh reservations about Acer's materials, feeling that it's kind of out of date. It's um whatever. Okay. So, you know, they're older materials. Obviously, they're older and so they're less in tune with the current exam, but they're still helpful. They'll still get you to practice um doing um equation manipulation, graph analysis. It'll still get you to do some things, not as well as their more recent materials. um you know, GAMSA practice tests one, two, three, uh and the online exam, which is their most recent materials and of course if you if you have gold standard practice materials, then of course our materials are always kept uh up to date to reflect uh current trends. Okay, so now let's get you equipped so that you can uh start the practice questions. By the way, when you're completing the practice questions, if you if you want to uh Google AI, uh call a friend during the time in which you're completing your project, do anything you want to solve the question. Um it's more important that than you bend your mind to the problem and try to find a solution than you just wait for the work solution and then see it because when you see the work solution of course it kind of makes sense. Um the important thing is the struggle because uh Acer's objective for both the humanities section and for the sciences section is to present new information to you and then to get you to struggle through it to find the solution. It's like continually presenting you with puzzles uh to solve. It's not that those puzzles require extensive background information. Uh, you know, there's a few things here and there. You know, that's life. But, uh, the great majority of the puzzles, um, sufficient information will be presented to you, uh, in order to solve the problem. And that's what's going to happen to you, um, during this uh, tutorial. And then you will be able to see how that reflects real past uh, GAMSAT exam questions. Okay, so some of you already have an account. You can go to gamsreprep.com and log into your account. Some of you never been there. It's just a free account, don't worry. And so, uh, Viv, if you can, uh, please put the link for the free exam. And, uh, so, basically, you're going to register for the free, uh, test. And, uh, then we're going to, uh, go to the test page together and at the same time. And, uh, and then we'll go to the science sciences section. Please don't complete humanity's questions during this tutorial. will be doing the sciences section and we will be completing uh these uh questions. So if you've never been on campsite.com, you're going to get access to a fulllength mock exam for free with all the work solutions for free. Um but we're going to be completing only these questions. So log in um go to um once you have logged in click on tests in the top menu or uh in the tab click on tests and scroll down to see this exam GS free the sciences section and once we have everybody there then we will um uh we will have a 12 minute uh clock. Not yet. Not yet. Viv, we'll have a 12m minute clock and then we will begin during the tutorial. If you are struggling, if you're uh having some connection problems, registration problems, uh whatever, uh you can just go to gamsrep.com and you know any of those links that you see in the chat and then you will see that there's a live chat button and you can ask your you can click on that live chat button to ask a question and to get a solution. Okay, I'm just going to wait one more moment and uh then we will set up our clock for 12 minutes to complete these six questions. So that's going to be your average. um you should pay very careful attention to that average uh for humanities and for sciences 1.5 minutes per question for the humanities and uh and uh that means uh for the humanities every um 30 minutes um you know you you everybody's going to be different. Everybody's going some people will be checking every 15 minutes, every 30 minutes, but whatever it is, you should have a regular um interval that you're you're checking your time to ensure that you've completed the correct number of questions and uh you should be doing that as well for obviously for for the sciences. So you have two minutes per question for the sciences. That means every 30 minutes you should have uh completed 15 questions. and um and for humanities 20 questions. So when you you keep checking and then you skip difficult units or challenging units. uh you just randomly guess because you're not penalized for guessing and then you do your best the clearest thinking you can perform on the units that you uh um are familiar with or or um you know graphs, tables, diagrams, things that you've practiced for. Okay, so that's enough blah blah blah. We're going to do our uh 12 uh minutes. So, I hope that you have click uh you've logged into gamsarprep.com. You've clicked on tests in the top menu. You've scrolled down and um uh found the test GS free this one and no other. The sciences section, not humanities, not written communication, which you've completed already. And then you um uh you will open the exam. and you'll start the exam and these are the questions that you'll be completing. Question 21 and 22 and 21 and 22 it's you're going to see a mathematical matrix. Okay? So, it's going to look like this and then uh you're going to have 27 and 29 and then question 55. Okay. So, and just in case you're pulling your hair out and you're struggling, um I'll ask Viv if she can uh please uh also put a link um to a PDF of the questions so that if people came late and whatever and then uh they can just complete the questions then they can log in to get the work solutions. Okay. So, 12m minute clock please. You will have these six questions to complete in the next 12 minutes. Just getting the clock set up and please begin. Good luck. Okay. So that's the time pressure that you have during exam day. So that gives you a little idea. Of course, you are permitted to have two A4 sheets of paper. Um, so two regular size sheets of paper on your desk to complete your calculations and so on. If you were almost finished one of your calculations, just finish it. Just complete your calculation. No. Uh, no problem. Now once you have uh completed these six questions, now I have to, you know, warn you. Um there's probably a couple of those questions that you thought you knew the answer to, but uh yeah, that's not how it works. So uh so it's possible that most of these questions, these six questions, it's possible that most of them uh you got incorrect. That's okay. It's better that that happens today and now and that you understand the tricks uh than it happens on exam day, right? So, uh, you know, don't worry about it. And one other thing I do want to mention is if for whatever reason, you know, you've been studying for a long time, you've gone through a lot of practice questions and you end up getting most of these questions right, like you end up getting four, five or six correct, then um, I have a challenge waiting for you for question 75. So you can reopen the exam and uh go to question 75 and uh I'm sure that will humble you and yet it is still uh based on current trends. So uh you'll have a new puzzle. So click end test. Uh so it's at the bottom um of your screen and if you didn't log in for the exam then um log into gamsprep.com and click on tests in the top menu. Scroll down to GS free and you can complete this free test as often as you want. So you can just work on a few questions here or there. It's no problem. Um you can complete it as often as you want. So you click on end test. Then go back to look at the solutions to these uh six questions and be humble and learn. And um I'm going to wait a few minutes and then I will uh discuss some key issues with regards to these three units. Okay. So, I'm going to go over some principles from these questions. Um, you will still be able to go through the work solutions later and uh, you know, and identify what went wrong. As I said before, if you got most of the questions right, just go to question 75 and work on that, you can reopen the exam um and then uh you know be able to see the question without the answer, work out the answer and then go through the solution. So this first unit is about converting. First of all, there's really no um assumed knowledge here. This is a puzzle and that's all there is to it. And uh there's going to be many puzzles presented to you as graphs, tables, and diagrams. And so this is just a puzzle. And uh uh let's just say we were generous in giving you the information before the question because um if you uh use the Acers's latest exam uh questions 73, 74, and 75, they don't set it up with so much information. Um so it makes it even a greater puzzle. But nonetheless uh this setup allows you to understand that there are columns. You see the columns and there are rows and we can identify um you know the column and the row with a specific number. Uh for example, this is the matrix. Um and we are looking at uh the first uh row in the second column there's the number four. So the matrix um in the uh first row in the second column there is the number four. And so that gives you just a general sense of it. And then here's a molecule and the molecule is simplified into um of course you should have a sense of this. It's common in organic chemistry not to include the hydrogens. And so we are looking at the connections between the carbons and by just looking at the connections between the carbons if we give them all a number. So we uh give this uh carbon number one these 2 3 4 5 6 7. So these are the seven carbons. Then we can uh create this matrix a mathematical matrix which is like a puzzle um which will identify which carbon atoms are touching which other carbon atoms. So uh in looking at this, let me just get a bigger view. So because there are seven carbon atoms, there's going to be a 7x7 matrix and this will identify whether or not the uh carbon atoms are touching. It's either touching another atom or it's not touching. So it's going to be one or zero as the possibilities for the adjacency matrix. So two things are adjacent or or touching uh each other. So is carbon one touching carbon one? No. Of course carbon one is touching carbon 2. So when when you look at this matrix, you're going to see zer's straight down the diagonal because um because a an atom is not adjacent to itself. It's not next to itself. It is itself. So when you look at column one, row one, it's going to be zero. Column two, row two, it's going to be zero. So that's always going to be because uh an atom is not adjacent to itself. So what is atom one adjacent to next to? It's only next to atom two. So here we have in the first row we have the number one representing that atom one is adjacent to atom two and it is not adjacent to any other atom in the molecule. So atom one is next to atom 2 but it is not next to any of the other atoms adjacent. So the next atom over. So that's why we get the number one here and the number one here representing atom one, atom two, atom one, atom two. So in these matrices, it's always going to not only be zero down the diagonal, but the top portion is always going to be exactly reflected in the bottom portion because of the symmetry. It's a 7 by 7 or 8 by 8 or 3x3 or whatever it should be. So now we are looking for in uh in our in the question we're looking for X and Y. Question 21 X and Y. So here and here we're trying to find out what they are. Well atom two we can see atom 2 is adjacent to two atoms one and three and is not adjacent to anything else. So atom two adjacent to one and three and nothing else. So atom two adjacent to one and three and nothing else. So y has to be zero. This also has to be uh uh zero as well. So this is atom two going down here. It's adjacent to one and three and nothing else. X and Y must be zero. So the answer to 21 must be C. And you can go through the work solution again uh later. And of course this is being uh recorded so that you can um you can watch the video on YouTube later if you wish. Okay. And then the next one is not adjacency whether or not it's next door to the atom or not. The next matrix is distance. So how far is the atom from the other atom? Example, atom one is one spot away from two, two spots away from three. One, two, three spots away from four, and six. Look, one 2 3 1 2 3. Let's see if that's reflected. Atom one is zero spots away from itself. One spot, this is row two, away from two. Two spots away from one, two, three. Okay. Two spots away from three. One, two. And now it should be three spots away from four and six. So this is one. This is row one, two, three, four. Three spots away. Five, six. Three spots away. So, three spots away from four and six. Four spots away from 1, two, three, four, five and seven. Four spots away from five and seven. Here's one. One, two, three, four. One. One, two, three, four. four spots away from five and seven. And it's reflected here. Again, zeros down the diagonal. The up reflects the down. Okay. So, now I'm going to uh look at uh Adam one, two, three. And I'm going to go down this column. column three. So this is atom three. Atom 3 is one away from two, four and six. Atom 3 is one away from two, four which is s and six. S is equal to 1 and that 22 the answer is C. Okay. And if it's the first time you've ever seen this, of course, you know, it, you know, could be challenged, but wouldn't you rather see it today than on the real exam and never have heard of a mathematical matrix or how it could be used for organic uh chemistry. So, and now is a wonderful time by the way u if you have access to Acer's online test uh to try questions 73 to 75. So, if you understood this then those questions should be super easy and those are the most recent released real past exam questions. Okay. So, let's take a look at uh questions 27 um to 29. And um you know in 27 to 29 question 27 uh 38% of students who sat this test got question uh 30 uh 27 correct. And I am sure that 90% thought they had it correct but but only uh 27% actually uh got it correct. So this is this is because of a misunderstanding with regards to um exponential scales. So when you're looking at a graph you you always look at the caption. Sometimes Acer has a caption, sometimes they don't. Sometimes they just write figure one you know but sometimes they give a little bit of information time kill curves incubate in the presence of various antimicrobials and a signifies antimicrobial alone. So that's the information given uh then you look at the scales you see this is a regular scale we call this linear because it's the same interval. uh the number two the number two number two number two it's always the same interval and um of course you you you look at the uh labeling of the graph this is time and this is CFU per mill and then you look at the scale here now it looks like it's regular intervals it appears to be but then you notice this is an exponential scale and that changes all the rules rules. How important is this to Acer? I'll tell I'll let you know. So, Acer released, of course, when you register for the for for GAMSAT, you get access to one free um ebook, which is Acer's Gamsat practice questions. It's their oldest ebook. It's from the 1990s, believe it or not. Um so, the questions are a bit old, but it's still okay. But the most recent free um practice questions that Acer released is in a video format. And uh let me just and I'm just getting you the link now. These are the most recent questions that Acer has released. They released them for free. It's only a few questions, okay? So, I can't get too excited. It's only a few questions, but um Acer could have asked any practice questions they wanted. If they're just choosing a few questions, what unit would they choose? organic chemistry, physics, would they choose general chemistry, titrations, titration curves? No, they chose a type of graph which is testing exactly what this graph tests, which is your understanding of an exponential scale. That's what it's doing. So that is what Acer chose as their only most recent sciences unit that they have made available for free. And so I put the link for you there and you can look at uh the one unit in sciences and the one unit in humanities which they have released. Okay, get back on track. Okay. Um so so yes uh in looking at this uh graph according to figure one the largest drop in the number of viable bacterial cells between hour one which is over here and hour 10 occurs with which of the following trials? And uh and really in terms of a drop, we're really just uh looking at uh the antagonist, which are these dark uh triangles, and synergistic, which is the dark squares. So here we have a obviously this is not a drop you know between hour 1 and hour 10 but here we have a drop and here also we have a drop and so uh what most people did uh 58% of people who looked at this question did is they eyeballed it they they looked at hour one to hour 10 and they see this is a bigger drop then our one to our 10 for the dark triangles. So then most people uh chose D as the answer which was uh synergistic. But um not the this is not even close to because when we we're looking at the drop in numbers at hour one synergistic is starting at a thousand. So this is uh 10, 100, a thousand. It starts at a th00and and it goes down to zero. Now let's see what this dark triangle is doing. Now this is a th00and 10,000 100,000. This is a million and this is 10 million. Dark triangle starts between a million and 10 million and it goes down just a little bit but perhaps it goes down to a million possibly it goes down to this level around a million. It doesn't matter. The point is it starts with some number between a million and 10 million and it drops. That means it dropped millions and this dropped a thousand. Absolutely no comparison. And so here's a question. You can read textbooks in biology, but if you're not completing problem based learning for GAMSAT, then you're not going to experience the type of questions that you can expect on the real exam. So uh so the answer is clearly B. It's clearly the antagonist that drops more and it's because it's an exponential scale. And here's a concept for you to remember um when you're completing the question that I put uh from Acer in the link and also some of their um real past exam questions is that uh small changes at the upper part of an exponential scale are far more important than large changes at the bottom part of an exponential scale. I'll say it one more time. Small changes at the upper part of an exponential scale are far more important than large changes at the bottom part of an exponential scale. And the next questions uh oh by the way in the work solution to this question I also cross-referenced um uh one of ACER's real past questions not just the videos because that came out uh more recently but from Acer's GAMS practice test one where they uh they have a unit that uses that same concept. Okay. So next um of course you know this same concept is going to be hammered home again and again. So anytime you see an exponential scale you should have a alert that um uh that might be the basis of the questions. So uh now we're looking at question 28 at hour six which is here. Which of the following best approximates the difference in viable bacterial cell numbers? um between the control and antimicrobial alone. So between control which is here and antimicrobial alone uh which is here. And so here less than half of people were getting uh the correct the correct answer. And so um let me get a little paper. So at at hour six hour six for uh for control we have 10 to the 9. So 10^ the 9 which is 1 1 2 3 1 2 3 1 2 3. So that's nine zeros. And I want to know the difference between this and so that's control and antimicrobial alone which is this one and we can say that's approximately 10 to the 4. So one two three four zeros. This is the difference and this answer when you look at the options that you have as possible uh solutions the answer is approximated by the original number. So why did people make mistakes and why did 40% of people choose B? It's because they took 10 10 to the 9 and uh 10 to the 4 and they divided them. They divided these two numbers. The question was what is the difference between these two trials? But if you divide them oh yeah so you get 10 to the five. Okay. And uh and that gives you answer choice B. But that's not the question. The question was what's the difference between these two? And uh again when you look at GAMS practice tests one um you'll see that uh they they pose the question for you to identify the difference between two trials. Okay, I think we're we're almost uh done for time. Um again you can uh look at question 75 um on the uh at the end of the exam and if you have any questions about any of the questions on the exam even though this this fulllength mock exam which has humanities and sciences is free you can post your questions in our forum. So we have uh gamsprep.com. Uh you'll see a forum link. You can find the test because we we have many fulllength exams. We have uh over 15 full-length exams. You can find the test which is GS free sciences. You might find that some student already asked a question on uh the particular question you want to ask. So you might find a um um you know a question that has already been asked. If not it's free for you to post and uh you can ask your question for any clarification that you might have. I hope you found these questions helpful. I hope you find that link ters questions helpful. Um I have another tutorial starting now. So good luck with your studies and um uh you know I hope you are able to achieve uh what you need and if not uh you can join us in our free tutorials which we have every month um uh going into the March exam and we also have uh three-hour tutorials starting in December and they will be weekly three-hour tutorials starting in December um which will go right up until the March exam. Good luck with your studies and bye for