The 3 Most Common GRE Trick Questions (in the GMAT and many other tests too!)

Summary

This video tutorial addresses common trick questions that frequently appear on standardized tests like the GRE and GMAT. The instructor highlights three key traps to avoid: the importance of 'distinct' in integer problems, the potential for decimals when 'numbers' are mentioned instead of 'integers', and the assumption of positive integers without explicit statement. Each trick is illustrated with a sample question, emphasizing the need for careful reading and logical deduction. The video encourages viewers to practice these concepts to improve their test scores.

Takeaways

• 📚 The video discusses common trick questions that appear on the GRE and GMAT exams.
• 🔍 Students often fall for these tricks due to overlooking specific wording in the questions.
• ✅ The first trick involves the word 'distinct' which implies that x and y cannot be the same number.
• 🤔 The second trick highlights the difference between the words 'numbers' and 'integers', where 'numbers' can include decimals.
• 🧐 The third trick points out that without the word 'distinct', x, y, and z could all be the same integer.
• 📉 The importance of understanding the question's wording is emphasized to avoid common mistakes.
• 📈 Practice is crucial to recognize and avoid these trick questions under exam conditions.
• 💡 The video encourages viewers to pause and try the questions themselves to test their understanding.
• 👍 Positive feedback and comments are encouraged to support the channel and potentially lead to more videos on similar topics.
• 🚫 The script warns against assuming that variables are positive without explicit mention in the question.
• 🎯 The video concludes by stressing the necessity of practice to handle such trick questions effectively during the actual exam.

Q & A

What is the main purpose of the video mentioned in the transcript?

The main purpose of the video is to cover the trick questions that are most likely to come up in the GRE, and potentially in the GMAT, to help students avoid common mistakes.

Why is the word 'distinct' important in the first trick question about integers x and y?

The word 'distinct' is important because it means the integers are different. Without it, x and y could be the same number, which changes the outcome of the comparison between quantity a and quantity b.

What is a common mistake students make when dealing with the first trick question?

A common mistake is assuming that x and y are distinct integers without the question explicitly stating so, leading to incorrect conclusions about the comparison of quantities a and b.

In the second trick question, why is the word 'numbers' instead of 'integers' a red flag?

The word 'numbers' instead of 'integers' is a red flag because it implies that the values can be decimals, not just whole numbers, which changes the possible range of the greatest numbers that can be chosen.

What is the trick in the second question regarding Nicole choosing three distinct numbers between one and five?

The trick is that the question allows for decimal numbers, not just integers, which means Nicole can choose numbers very close to five, making the product much larger than 64.

Why is it a mistake to assume that x, y, and z in the final question are positive integers?

It's a mistake because the question does not specify that x, y, and z are positive. They could be negative integers, which would significantly change the sum in quantity a.

What is the correct sum of x, y, and z in the final question if they are all positive integers?

If x is 23, y is 1, and z is 19, the correct sum of x, y, and z is 43, which is greater than quantity b.

What is the potential error in the final question if x, y, and z are considered to be negative integers?

If x, y, and z are negative, their sum could be much less than 42, making quantity a smaller than quantity b.

What does the video suggest about the importance of practice for GRE and GMAT test takers?

The video suggests that practice is essential for test takers to be aware of and avoid falling for trick questions, even under exam pressure.

What can viewers do if they enjoyed the video and want to see more content like it?

Viewers can leave a like and a comment to show their appreciation and provide feedback, which may encourage the creator to make more videos on similar topics.

Outlines

00:00

📚 GRE Quantitative Reasoning Trickery

This paragraph introduces the video's focus on common trick questions encountered in the GRE Quantitative Reasoning section. The tutor emphasizes the importance of being aware of these tricks, especially when they might also appear in the GMAT. The audience is encouraged to pause and attempt the questions before the tutor reveals the answers. The first trick involves a quantity comparison question where integers x and y between zero and five are compared in absolute value to 0.99. The common mistake is assuming x and y are distinct without the question specifying so, leading to incorrect assumptions about the comparison.

05:01

🔢 Decoding GRE and GMAT Quantitative Traps

The second paragraph delves into a specific trick question where Nicole picks three distinct numbers between one and five, and the challenge is to compare the product of the three greatest numbers to 64. The common mistake is assuming the numbers are integers, missing the fact that the question allows for decimal numbers, which can significantly alter the outcome. The tutor highlights the importance of reading the question carefully and not being misled by the typical range of integers. The audience is also encouraged to like and comment on the video for more content on similar topics.

Keywords

💡GRE

GRE stands for Graduate Record Examinations, which is a standardized test that is an admissions requirement for many graduate schools in the United States. In the context of the video, the GRE is the subject of the discussion, as the tutor is addressing common trick questions that appear on this exam.

💡Tricky Questions

Tricky questions are those designed to test not only knowledge but also the ability to think critically and avoid common mistakes. The video's theme revolves around these types of questions, with the tutor explaining how students often fall for them on the GRE and GMAT exams.

💡Quantity Comparison

A quantity comparison question is a type of problem where the test taker must determine which of two quantities is greater, or if they are equal. The video script uses this term to describe a specific format of trick question that appears on the GRE, where students must compare the absolute value of 'x minus y' to '0.99'.

💡Absolute Value

The absolute value of a number is the non-negative value of the number without regard to its sign. In the script, the tutor explains how absolute values work and how they can be used to solve a trick question involving integers x and y.

💡Distinct

The term 'distinct' refers to being different or separate from one another. In the context of the video, the tutor points out the importance of this word in trick questions, as it indicates that the variables involved cannot be the same, which is a common oversight that leads to incorrect answers.

💡Integers

Integers are whole numbers that can be positive, negative, or zero. The video emphasizes the distinction between 'integers' and 'numbers,' which can include decimals. This distinction is crucial in trick questions where the wording can lead to incorrect assumptions about the range of possible values.

💡Product

In mathematics, the product is the result of multiplying two or more numbers together. The video script uses the term 'product' in the context of a trick question where the tutor explains that the product of three distinct numbers chosen by Nicole must be considered in relation to the number 64.

💡Decimals

Decimals are numbers that have a whole number part and a fractional part, separated by a decimal point. The video highlights the importance of considering decimals in trick questions, as they can be overlooked when the question uses the term 'numbers' instead of 'integers.'

💡Prime Numbers

Prime numbers are natural numbers greater than 1 that have no positive divisors other than 1 and themselves. The script uses the prime numbers 23 and 19 as examples to illustrate a trick question where the unique factorization of primes leads to a specific solution.

💡Negative Numbers

Negative numbers are numbers that are less than zero. The video script warns about the common mistake of assuming all variables in mathematical problems are positive, which can lead to incorrect conclusions in trick questions where the variables could be negative.

Highlights

The video discusses common trick questions that appear on the GRE and GMAT exams.

The presenter advises pausing the video to attempt the trick questions before the answers are revealed.

The first trick involves understanding the importance of the word 'distinct' in a quantity comparison question.

Students often miss the nuance that 'x' and 'y' could be the same number, leading to a wrong answer.

The second trick question involves choosing three distinct numbers between one and five, with a twist on the word 'numbers' versus 'integers'.

Decimals can be considered as the greatest numbers, which is a common oversight.

The third trick question involves prime numbers and the assumption that variables are positive integers.

The importance of recognizing that variables could be negative integers is highlighted.

The video emphasizes the need to practice under pressure to avoid common mistakes.

The presenter shares a personal anecdote about making a mistake due to overlooking negative integers.

The video encourages viewers to be 'paranoid' about the tricks that standardized tests may use.

The presenter suggests that even if viewers recognize the tricks, practice is essential for exam success.

The video concludes by congratulating those who got the trick questions right and encouraging continued practice.

The importance of understanding the wording of questions in standardized tests is a recurring theme.

The video provides a detailed explanation of how to approach and solve trick questions effectively.

The presenter's teaching style is engaging, aiming to help students avoid falling for common test traps.

Transcripts

almost every week while tutoring i see

my students

fall for one of these three tricks so i

thought i'd do a video

where i just cover the trick questions

that are most likely to come up

in the gre of course there are many

other types of trick questions

and these particular tricks might also

be tested in the gmat

but i just wanted to cover these three

ones quite quickly in this video

an obvious recommendation for this video

would be for you to pause the video

and give your honest answer i know

obviously you're expecting a trick

question

but i might have tricked you and there

might not be a trick so either way

try yourself and see what you would have

honestly picked before i tell you what's

what

and if you can see through these three

trick question types

and get them right you're a big step

towards

a good score okay let's do this one

x and y are integers between zero and

five

what's bigger quantity a x minus y in

absolute values

or quantity b 0.99

and this is a quantity comparison

question which

is in the gre where you need to say

which one's bigger a

or b or they're the same or d you don't

know

now obviously if this came up in the

gmat or a different exam it wouldn't be

phrased as a quantity comparison

but the same core concept would be

tested

so what's your answer what a lot of

people would do

is try out numbers and they would try

out

five and zero and then notice that five

minus zero

is five and the absolute value of five

is just five

so quantity a is bigger by the way the

absolute values which i've covered in a

different video just

turn what's inside into a positive if it

wasn't before

so to do another example if x was 3 and

y was 5

3 minus 5 is minus two but the absolute

values turn the minus two into a two

so again quantity a is bigger and after

a while people would

see that the numbers they're picking

always give quantity a as being bigger

and then pick one to a the mistake of

course

is that the question never used the word

distinct

and that's an important word that they

missed out they didn't say x and y

are distinct integers and the word

distinct means different

they're different integers because they

didn't use that word distinct

we don't know if x and y are just the

same number

it could be that x is three and y is

three

in which case three minus three is

and the absolute value of 0 is 0 making

quantity b

bigger so the answer would be d because

they didn't use that word distinct

we don't know if they're not just the

same number twice

so watch out for the word distinct they

sometimes might use the word different

which is a simpler word but either way

those words are needed

for us to know that they're different

integers not just the same integer twice

right that's the first trick feel free

to pat yourself on the back if you got

that right

if not brilliant because you just

learned something from this video

so let's move on to the next trick

question

nicole will choose three distinct

numbers between one and five

inclusive quantity a is the product

of the three greatest numbers she can

choose and quantity b

is 64. so here in this question we can

see that they have used the word

distinct

which means that the numbers she's going

to pick can't all be the same

quantity a is the three greatest numbers

she can choose

so that would be three four and five

inclusive means including one and five

including the bottom end of the range

and top end of the range so most

students will go

3 times 4 times 5 is 60

and that's smaller than quantity b which

is 64.

so quantity b is the bigger one

the trick here very common trick by the

way in the gre

and the gmat is they use the word

numbers

not the word integers that's a big red

flag

the question said that nicole will

choose three distinct

numbers not three distinct integers

so don't be fooled by the whole it has

to be between one and five that doesn't

mean

the numbers in that range are all going

to be integers so what are the three

greatest numbers

that she can choose well 5 4.999

recurring

and 4.998 for example

they can be decimals because the

question

didn't say integers it said numbers

so the three greatest numbers she can

choose are all essentially five now i

know it says distinct

but you could call one of them five one

of them four point nine recurring

one of them four point nine nine nine

nine nine eight so essentially in terms

of the mathematics

they're almost all five just under five

times five times five

which would be 125 that's five times

five times five five cubed

so given that they have to be distinct

they can't all quite be

five then it's going to be a shade under

125 but either way that's much bigger

than quantity b

which is 64. so quantity a would be

bigger again the trick here that many

people miss

is when the gre uses the word numbers

instead of using the word integers or if

they don't use any word at all

just be aware that decimals are a

possibility

by the way if you're enjoying these

tricks or you've learned something so

far

please do leave a like and a comment it

really does help the channel out

and if i get enough feedback from this

video i'll do future videos on other

common tricks that they can ask you in

the wording of questions

here is the final question the final

trick question

x y equals 23 and y z

equals 19. x y and z are

integers quantity a x

plus y plus z the sum quantity b

42. now even though they didn't use the

word distinct

we can know a few things here right 23

and 19 are primes that's always good to

spot

and because 23 and 19 are primes there's

only one way to get to them

it can't be five times six or anything

like that to get to 23 it would only be

1 and 23. now we wouldn't know

necessarily which way round it was 1 and

23 or 23 on one but we would know it's

that combination

same thing for y times z 1 and 19 gets

us 19 or

19 and 1 but we wouldn't know which way

around but then the more observant

students

would say themselves ah it must be y

that's one

because y appears in both products so it

must be that x is 23

and y is one and again y is one and z is

19.

otherwise if y was 23 for example in the

first equation

then that wouldn't make sense for the

second equation so

there we have it there we have the three

numbers and with those three numbers

we can add them up 23 plus one plus 19

is 43 i believe making quantity a bigger

a trick and i know some of you are now

screaming at the video

telling me what the trick is is that it

never said

that x y and z are positive

a very classic mistake i remember in my

final practice test before the real

thing

i got one of the questions wrong based

on forgetting that they could all be

negative

so i don't want you to make that same

mistake it could be

i was kind of tricking you in the way i

was saying it but it could be that x

is negative 23 and y is negative one

negative 23 times negative 1 does get

you positive 23.

likewise y would be negative 1 and z

would be negative 19

and they multiply to get positive 19.

notice

the question never said that they're

positive integers they just said

integers

and so if all of them are negative x

plus y plus z

is way lower than it's like negative 43

which is a lot smaller than positive 42

making the answer d now finally to those

people who got all of them right

congratulations but i would say can you

get them right

in the exam under that pressure and

that's why this kind of practice is

essential

even if you spotted these tricks and the

trick questions

it's still important to practice and be

almost paranoid

about the kind of tricks the gre gmat

and other tests can throw at you

don't be like me getting questions wrong

even though you know the topic

and for those of you who learned

something i'm really glad you watched

the video

either way to all of you see you in the

next video