Tyler York

February 14, 2022

For variable-based problems on the GRE quant (ie “if x<5 and y>3, then..”), you can “plug in” numbers to test the answers out and see which are even *feasible *to be correct. But not all “plug in” numbers are created equal – some are much more useful to use than others for eliminating wrong answers and ensuring you don’t fall into any traps. We shares our hierarchy of the best plug-in numbers to use on the GRE quant.

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1.0s Welcome to GRE snacks. Snackable episodes School admission. I'm Tyler founder Chief and I'm a Ryan founder of Stellar GRE inauthor, to the Bulls GRE course. 22.2s You can check out our course at achievable. And decode podcast. Could you 10% off a check it out. Let's get started. 29.6s So today we're going to be talking about the best numbers to plug in on GRE Quant questions which kind of ties into some of the things you talked about the GRE Quant earlier about how you should be. No try to eliminate answers, really on things like that. So, tell us a Ryan. What are the best numbers to plug in what plugging in actually is? Cuz I don't know if that's them fairly obvious to every listener, use on the quantitative section that in the solar system we use, when we encounter a structural specific structural diagnosis, where we see that, the answer choices of the questions have variables in them usually letters like things like that. 82.2s We want to dispense with as much algebra as possible. And if we use strategies like the plug-in Technique, we can get rid of 99% of the algebra on the GRE and let me tell you that is a very, very good thing because I have yet to encounter myself included, anybody who is more accurate and efficient doing algebra than they are doing arithmetic. So how does this work? Is basically where we replace abstract. Variables with concrete values. Actual numbers. Why can we do? This, will think back to your 8th, grade algebra, a variable represents many, many different numbers. If I were to say that X is greater than zero, there is an Infinity of numbers that I could be any positive number could be a Million numbers. It could be and 140.0s That just is enough to make our little human monkey brains. You know, slow, it's very difficult to think about the infinite possibility that most variables represent a table represent every number in a given domain, then any number that we choose should work because any is always a subset of every. So basically we're going to dispense with the every and just choose any number that works and use it as a kind of a substitute for the infinite variety of every. Okay, so we need to do this whenever we see variables, the answer choices and rather than do Algebra pick our own numbers. 183.6s In general, it's a good idea to pick nice easy numbers that have short ate our calculation. So the niceties his number of all, what do you think, Tyler? Any ideas on what is weird? We'll get to that in a second positive. It's an integer even we use it all the time. It's very easy to do, multiplication and division and subtraction so bored. And gone with with two sodas 3 for are generally. My go-to plug-in values especially on a first round and sometimes you have to plug in more than one. 229.8s There are some exceptions. For example, if the question includes the word percent or has it % somewhere in it, what do you think the best number to choose there might be, Tyler like 10%. 241.5s 100. What is 3%? / out of send $100. Right? Or hundred. What's 37% of 100? 257.4s 37, exactly. What's 42.1% of a hundred for a different one. If you. So, there are some exceptions to the small positive integers, like to 34 Langley percentages, but in general, you want to choose values that make your life easy. We have to plug in more than one in particular, we have to do this, when we're encountering quantitative comparison, with what you need to the GRE, they give you some information and they give you two values, one inquiry. A one of which is bigger are like, you know, a + b /. C versus like, you know, she posed to be divided by a like that kind of thing. 317.4s Known. You could have two definite but unknown value. There's a few different permutations in that capacity but you see that there are variables at all in the answer choices to Clinton comparison question you want to do. You want to plug in twice? The first round? You want to plug in nice numbers? Like, we discussed to 3/4 in truth. We want to try to test the system want to stress the system to ensure that we get a consistent response. So I can, if we were scientists and we were kind of studying, you know, the kinds of environments are biomes in which life could live. It doesn't make sense to just go to like, a Tropical Islands like Hawaii. We have to go to Antarctica. We have to go to the Marianas Trench. We have to go to the upper Stratosphere to see kind of what is possible and stretch the limits of what life can, which wife can survive if we really want an answer that question. 377.8s Right? I also have called this then I mean at least the SAT like the reason why I brought up zero the number is because most of those math questions where zero is a possibility like it's like a Nexus between 4 and -4. Like there's a lot of times where there will be at least one in your choice that works with everything except zero and zero is the gotcha answer is true. So just rely on nice numbers. We fall into traps of, I call a path of least resistance, thinking if we just use numbers that are immediately obvious to us or simple to manipulate the test often sets of transfer students in that way. So how can we stay safe? When pregnant, 436.6s When sure that we're not falling for these like gotcha situations as you described and I've come up with a rank ordered weird number list, there's five number to type numbers on this list and Steve can just go down this list in our rank order fashion, whenever they're plugged in in these, in the situations that are appropriate to it. The weirdest number of all in the number one spot is number 0. A weird number isn't valueless value? It's like one hand clapping that number actually doesn't make sense. If you think about it and then it in fact, people have been doing that for thousands of years before it was invented as a as a mathematical concept. So it's not an obvious natural number as it were 486.6s 0 destroys now, you know, because of its identity properties. So easy to root. 496.3s Square 2000 square. 200. Powers want anything plus zero to self anything. So is the exception to every rule. So that's why we use it whenever we can. Because if we get a consistent response between using an ICD number, and the number that the exception to every rule, we know that we've kind of covered all of our bases for the basket. That makes sense, to keep in mind, is that just because you have different variables. Like an example, you gave it was like a + b, oversee because of your different variables. Doesn't necessarily mean that those variables represent different values. 537.5s A real clever thing to do is to plug in 0 for everything. You can make in your example as a b and c all 0. 2 0, / 0, / 0, / 0. I think it's just a zero. I think, I think that's the one time you for everything. A generally either destroys Matt like a / 0 situation or it makes the math really, really simple because it collapses on itself, right? Exactly. That's why you're at the top of our list. If we can use it, we should always use it in the number two spot is the number one, which is very annoying for the number one, but whatever is how it is. 585.8s And the reason why one is in the two spot is the same reasons are in the one spot, is because there's a lot of strange identity properties. Associate won the first Power self-raising, * 1 /, wanted to sell. These are very unusual in the universe of mathematics. In fact, Michael system that students studying in Western culture is built on a true and from that point we can build the entire castle of mathematics. The first max Axiom this, like the number zero, existence is what 0 does second. And the third option is, you can add things. And basically everything for me, what the fourth one is, but everything from simple arithmetic, to Advanced calculus is based upon these for 645.7s Turn people black back to the, we have zero, we have one and then in the free spot are numbers between 0 and 1. 657.2s Not entice people refer to these as decimals and fractions I'm going to be a math nerd and say there's nothing weird about decimals and fractions the number 2 in a decimal 2.0 as a fraction 2/1 to what makes the numbers between 0 and 1. Weird is not that they're usually expressed decimals and fractions but because they live between zero and one of the number line is like a haunted neighborhood. It's not their fault, it's just Where They Live Nation, do spooky spooky stuff, happens around exponents and radicals. Usually when you, you know, Square apposite number gets bigger, and when you routed a smaller, except when you're dealing with numbers between 0 and 150 square, root 1/4 becomes one half of these are great numbers. When dealing with radicals 713.0s Okay, 601, number streams are in one number for are negative numbers most because people forget about them and these are really important numbers to plug in. When kind of an example, you gave then zero is in the equation negative number over here to deposit over here. So the question is implicitly or explicitly testing you on ideas 736.2s And then number five is pushing the extremes. Which means either really really big numbers or really, really small numbers given the context of the problem and pushing the Extremes in the five spot because you can always use it even if you can't use zero even if you can't use one, even if you can't use numbers between here. And why didn't you can't use negative? Because of the domain of the problem and just like the example, I can about the biome strange, things tend to happen when we approached extreme condition. So that's my weird extreme examples. So you know you want to 780.6s Err on the side of using zero whenever you can because it's more likely to stress the system successfully. That makes sense though just to conclude first start with easy numbers recommendations are 2 3 and 4. Then start going through the weird numbers which are 0 1 between 0 and 1 and then the extremes I miss the negatives. I would love to have done five out of five. 819.7s Alright, well, thank you everybody. This is Ben, Jerry snacks hosted by a Ryan from Stellar GRE and Tyler. From achievable T-Mobile on a Ryan and partner to build a great. GRE course you can try for free at achievable. Me and use the code podcast to get 10% off at. Check out if you have a question or topic they like to discuss in the future. Episode please contact. Tyler at Tyler at at me with the subject line podcast topic.

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