Who Wants to Be a Mathematician Discussion
Go back to the Math Jam ArchiveAoPS instructor David Patrick will discuss the 2019-20 Who Wants to Be a Mathematician Championship contest. WWTBAM is a free(!) contest sponsored by the American Mathematical Society in which high school students compete for cash and prizes. Round 1 of qualifying for the contest will take place September 9-26, 2019, so this is your chance to learn about the contest, the type of problems that appear, and how to participate. We will be joined by Mike Breen and Bill Butterworth, the creators of the game. Mike is also the host of the Championship finals, to be held in Denver in January 2020.
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Facilitator: Dave Patrick
Time to get started!
Welcome to the 2019-20 Who Wants to Be a Mathematician Informational Math Jam!
I'm Dave Patrick, and I'll be leading our discussion tonight. Many of you know me from around AoPS: I've taught dozens of AoPS classes over the past 15 years, and I've written or co-written a few of our textbooks.
I also once was a contestant on ABC's Who Wants to Be a Millionaire back before I started working at AoPS, way back when Regis Philbin was still the host. Here's a picture (I'm on the left, Regis is on the right):
Photo Credit: Maria Melin, copyright 1999 ABC Television.
how much did you win
Sadly, I didn't win the million bucks, but I did win enough to buy a new car.
Before we get started I would like to take a moment to explain our virtual classroom procedures to those who have not previously participated in a Math Jam or one of our online classes.
The classroom is moderated, meaning that students can type into the classroom, but these comments will not go directly into the room. These comments go to the instructors, who may choose to share your comments with the room.
This helps keep the session organized and on track. This also means that only well-written comments will be dropped into the classroom, so please take time writing responses that are complete and easy to read.
We won't be going through the math quite as thoroughly as we do in our classes -- I can't teach all the material for every problem as we go.
Another difference between tonight and our regular online classes is that it is very unlikely that we'll be able to answer every single question you ask. We usually do in our classes, but we have a large number of students tonight! So, please go ahead and ask questions, but also please understand if we aren't able to answer them all!
Tonight we'll be discussing the 2019-20 Who Wants to Be a Mathematician Championship contest.
We'll spend a few minutes discussing how the contest works, and then I'll go over some problems from last year's contest.
Who Wants to Be a Mathematician (or WWTBAM for short) is conducted by the American Mathematical Society (AMS).
The AMS promotes mathematical research, fosters excellence in mathematics education, and increases the awareness of the value of mathematics to society.
The AMS is one of the two big professional mathematics organizations in the U.S. (The other is the Mathematical Association of America, or MAA, which as you may know runs the AMC/AIME/USA(J)MO contests.)
Joining us tonight from the AMS is the co-creator and host of WWTBAM, Mike Breen (mikebreen).
Good job with the logo and mission statement. Thanks.
Hello, everyone.
Mike taught at Alfred University and Tennessee Technological University before becoming AMS Public Awareness Officer in 2000. He and Bill Butterworth began Who Wants to Be a Mathematician for the American Mathematical Society in 2001, and the first national game was in 2010.
Mike has been a contestant on Jeopardy! and Wheel of Fortune (if you want to know if he won lots of money on either show, note that he is still working for a living) and may be the only person ever to cut his hand on the wheel. Who Wants to Be a Mathematician has so far been much safer.
Bill Butterworth (TPiR) is with us tonight too. Bill earned an undergraduate degree in mathematics from Santa Clara University and a Ph.D. from Northwestern University, and is currently an associate professor and associate chair of mathematics at DePaul University.
Welcome everyone
Can you guess what Bill's username stands for?
The Price is Right
The price is right
Correct! In addition to authoring articles and presenting talks related to game-show mathematics, Bill served as mathematics consultant to the CBS television show The Price is Right from 1997 to 2009. (Hence, his username.)
Bill shares a life-long interest in game shows with colleague Mike Breen, with whom he works as the not-so-lovely assistant on Who Wants to Be a Mathematician.
So between the three of us, we have a lot of game show experience!
Assisting for us tonight is Brent Nicklas (brentnicklas), who as far as I know hasn't been on any game shows.
Brent first joined AoPS as an assistant in 2013. He received bachelors degrees from Michigan Tech in both mathematics and physics with concentrations in secondary education in 2014, then earned a masters degree in statistics in 2016. When he's not doing math, he enjoys drawing comic sketches, playing board games, cooking, riding his bicycle, and swing dancing.
Greetings! I have not been on any game shows, but I'm excited to be here!
We'll start with an overview of how the contest works. All of the information I'm about to tell you, and more, is on the WWTBAM web site at http://ams.org/wwtbam . There are also many years' worth of past contests on that website.
The WWTBAM Championship contest is open to students in the U.S., Canada, and the United Kingdom. Although the contest is designed for high school students, middle school students are eligible to participate too. Topics up to and including precalculus are included on the contest, so in terms of mathematical content, WWTBAM is similar to the AMC 12 contest.
Your school needs to sign up for the contest. You cannot sign up as an individual. But a homeschool counts as school too, so if you're homeschooled, your parent or other homeschool teacher can sign up.
The good news is that the contest is free to sign up for. The even better news is that every school that signs up will also get an AoPS coupon.
To sign up, your school (not any individual student) should do one of the following:
1. Go to https://wwtbam.mobius.net/instructor/ and fill out the registration form.
2. Send an email to paoffice@ams.org with the subject line "WWTBAM Championship".
My parent can sign me up if my mom is my homeschool teacher and she has no other students?
Yes, that's right.
Your school will then receive instructions for how to administer the qualifying test. Round 1 of qualifying will take place September 9-26 -- your school can administer the qualifying test on any day during this period.
Can middle school sign up for this test?
Yes, although the contest is designed for high school, middle schools may sign up too.
Must the school sign up before Sept. 9, or can they sign up during the testing perion
I believe you can sign up all the way until the end of the period, but I'm not 100% sure.
A lot of you are asking more specific questions -- please hold those until the end and Mike and I will try to answer them, or you can probably find the info you need on the website.
Qualifying Round 1 of the national contest will consist of 10 questions, with a 15-minute time limit. So the problems are quick: you have an average of 90 seconds per question. (But as you'll see a bit later when we look at some problems from last year's contest, some of the problems may not take you nearly that long.) No books, notes, calculators, or internet access is permitted during the test.
Any student who scores at least 7 out of 10 correct on Round 1 will be invited to participate in Round 2, which will be held in October. The format for Round 2 is the same: 10 questions, 15 minutes, except that Round 2 is short-answer instead of multiple-choice.
After Round 2 is complete, 12 students will be invited to compete in the Championship Finals, held live in Denver at the 2020 Joint Mathematics Meetings in January. Travel costs to and from Denver will be covered by the AMS.
Here's how the 12 finalists will be determined: 10 of the 12 will be the top scorer from Round 2 in each of the following regions:
The other two contestants will be the top scorer in the United Kingdom and the top scorer in the Denver metro area (or the second-highest scorer, if the highest scorer in Region 8 happens to be from Denver).
Since with only 10 questions there are likely to be ties for the top scorer, there will be tiebreakers if necessary. The first tiebreaker will be question #10 of Round 2: this question will be an "estimation" question that will be hard to get an exact answer for, but for which it is reasonable to try to estimate (or guess).
For example, last year's tiebreaker question #10 was:
10. A partition of a positive integer $n$ is a way of writing $n$ as a sum of positive integers. For example, the number $3$ has three partitions: $3$ (the number itself is a partition with one addend), $2+1$, and $1+1+1$ (the order of the addends doesn't matter). How many partitions does $101$ have?
This is essentially impossible to compute exactly by hand, but one can make an educated guess.
As it turns out, the actual answer is $\boxed{214{,}481{,}126}$.
If there is still a tie (which is unlikely), then a winner for the region will be selected by the contest organizers.
How did you figure it out??
how did you work that out?
You can take a look at last year's Math Jam transcript to see how we approached it.
Indeed, if you want to see all the problems from both qualifying tests from last year, along with worked-out solutions, you can read the Math Jam transcripts from last year:
Round 1: https://artofproblemsolving.com/school/mathjams-transcripts?id=470
Round 2: https://artofproblemsolving.com/school/mathjams-transcripts?id=471
The Championship finals are held live in front of an audience at the Joint Mathematics Meetings, and are also live streamed on the web. (You can watch the archives of past years' finals on the WWTBAM website.) Contestants will compete directly against each other in semi-final rounds, with the semi-final winners advancing to a Jeopardy!-style buzz-in final round to determine a champion.
All of the finalists will receive prizes (in addition to the free trip to Denver!), and the champion will win $10,000.
will we be figuring out problems like that later?
or just from round 1?
We'll be doing that right now! To give you some idea of the content and difficulty level of the contest, I'd like to present three of the problems from last year's Round 1 Qualifying Test.
Here is last year's #1:
1. What is the ones (units) digit of $2019^2 - 2018^2$?
$ $
(a) $1$ (b) $3$ (c) $5$ (d) $7$
Reminder: all the Round 1 questions are multiple-choice.
Please do not simply post your answer. Instead, please post suggestions as to how to solve the problem.
Modular arithmetic, modulo 10
We observe the units digit of both squares
First you can find the unit digit.
only units digits matter. so problem simplifies to $9^2 - 8^2$
difference of squares
difference of square
Difference of squares:a^2-b^2=(a+b)(a-b)
using difference of squares, we find (2019+2018)*1 so the units digit is 7
difference of squares
Right, there are a couple of ways to do this.
We could observe that the units digit of $2019^2$ is the same as the units digit of $9^2$, which is $81$. So its units digit is $1$.
Similarly the units digit of $2018^2$ is the same as the units digit of $8^2$, which is $64$. So its units digit is $4$.
d)7. This is the answer becaause 9 squared minus 8 squared is 81-64= 17. Therefore the units digit is 7
Right, or for example, $11-4 = 7$. So the units digit of the difference is $7$. $\boxed{\text{(d)}}$
Or, as many of you mentioned, we can use the difference-of-squares factorization!
We get $2019^2 - 2018^2 = (2019 + 2018)(2019 - 2018)$.
Very good.
This is especially convenient because the second factor is just $1$.
So the difference is equal to $2019 + 2018 = 4037$, and has units digit $7$.
About 3/4 of the students taking Round 1 last year got this question correct.
Next is #5 from last year, which is "medium" difficulty:
5. Which of the following is the closest integer to the cube of $\tan\left(\frac\pi3\right)$ ($\frac\pi3$ is in radians, not degrees)?
$ $
(a) $5$ (b) $6$ (c) $7$ (d) $8$
Again, WWTBAM is a high-school level contest, so trigonometry problems are fair game. Middle school students are certainly permitted to participate if they wish, but advanced high school topics like intermediate algebra (including logarithms) and trigonometry will appear on the contest.
First, what is $\tan\left(\frac\pi3\right)$?
Sqrt(3)
sqrt(3)
sqrt(3)
$tan(\frac{pi}{3}) = \sqrt{3}$
$\sqrt{3}$
sqrt(3)
Good!
60 degrees
TAN 60?
tan(60) degrees
Certainly, you might prefer to think of $\frac\pi3$ radians in terms of degrees.
The key is to remember that $\pi$ radians is $180^\circ$. So $\frac\pi3$ radians is $60^\circ$.
And then $\tan\left(\frac\pi3\right) = \sqrt3$. Think of a 30-60-90 triangle with legs $1$ and $\sqrt3$ and hypotenuse $2$. The tangent is the ratio of the two legs.
So the quantity we want to round to the nearest integer is $(\sqrt3)^3$.
or $3\sqrt{3}$ ;)
Yeah, a better way to write that is $3\sqrt3$.
3*1.7=5.1
i think that rounds to 5
Right: you may know that $\sqrt 3 \approx 1.7$ (and you can check that $(1.7)^2 = 2.89$).
And certainly $1.7 < \sqrt3 < 1.8$.
So $5.1 < 3\sqrt3 < 5.4$.
A
(a)5
a.) 5
So the answer is $5$. $\boxed{\text{(a)}}$
is a calculator allowed?
No. (This problem would be pretty easy with a calculator!)
Slightly over half of the students taking the contest last year got this correct.
Finally, here was #10 (the final problem) from last year's Round 1:
10. Which of the following is closest to the number of ordered pairs of points $(m,n)$, where $m$ and $n$ are both between $1$ and $100$ inclusive and relatively prime (their greatest common divisor is $1$)? [$(2,3)$ and $(3,2)$ count as two such points.]
$ $
(a) $5{,}000$ (b) $6{,}000$ (c) $7{,}000$ (d) $8{,}000$
So, there are $10{,}000$ ordered pairs in total. How can we count how many of them are relatively prime?
Only 25 possible prime factors to check
True: there are 25 primes under $100$, but what does it mean "to check"?
by subtracting all those that are multiples of a prime factor
Right, but to be more precise: we want to subtract those $(m,n)$ where $m$ and $n$ are multiples of the same prime factor.
Maybe we can count these. Or at least get an estimate that clearly rounds to one of the answer choices.
For instance: how many pairs $(m,n)$ are both multiples of $2$?
well about a quarter have two multiples of 2
2500
2500
Right: exactly $\frac14$ of them, or $2500$.
So we can eliminate $\frac14$ of our pairs, and we're left with $10000 - 2500 = 7500$.
How many of the remaining pairs have both terms multiples of $3$?
1/9 of the pairs
Right: about $\frac19$ of them. (About $\frac13$ have $m$ a multiple of $3$ and about $\frac13$ have $n$ a multiple of $3$.)
So we throw those away, and what's left is about $\frac89 \cdot 7500$.
but like arent we double counting like (6,12)
Aren't we overcounting?
That's a really good concern.
But we're not, because I'm only throwing away $\frac19$ of what's remaining.
So now we're down to about $6700$. And we've still got more to get rid of.
How many of the remaining pairs have both terms multiples of $5$?
1/25
1/25
1/25
1/25
1/25
1/25 of them
Right: about $\frac{1}{25}$ of them. (About $\frac15$ have $m$ a multiple of $5$ and about $\frac15$ have $n$ a multiple of $5$.)
So we throw those away, and what's left is about $\frac{24}{25} \cdot 6700$.
This is about $6400$.
We're throwing away fewer and fewer each time.
We'll throw away another $150$ or so ($\frac{1}{49}$ of $6400$) when we look at the $7$'s. Down to about $6250$.
We'll throw away another $50$ or so ($\frac{1}{121}$ of $6250$) when we look at the $11$'s. Down to about $6200$.
guesstimate of around 6000
Yeah, it looks like we'll end up somewhere around $6000$, maybe a little higher since there isn't much left to throw away.
Yeah...B
The answer is (b) 6000.
So b)
It seems clear that $6000$ is the closest of the answer choices. $\boxed{\text{(b)}}$
what is a rigorous way to do this question
This actually is rigorous! If we did this calculation more carefully, we might even get the actual answer, which is $6{,}087$.
how do we do that in 90 seconds?
So this was solved in ~1.5min?
Probably not...but then again, the early problems might not have actually taken 90 seconds each.
You might have gotten the $2019^2 - 2018^2$ problem much more quickly, for example.
And there's no penalty for guessing, so you can always make an educated guess.
By the way, does anybody know the general result for the situation in problem #10?
isnt it like probability 6/pi^2 or something
Exactly!
It turns out that the number of pairs $(m,n)$ of relatively prime positive integers where $m$ and $n$ are less than or equal to $N$ is approximately $\dfrac{6}{\pi^2} \cdot N^2$. (This requires some calculus to prove.)
And indeed, when $N = 100$, this formula gives $6079$ (rounded to the nearest integer), which is remarkably close. It's only off by $8$, which is within $0.13\%$ of the actual answer.
Who proved it?
I think it's generally credited to Euler.
And finally, here is a pretty picture I made. Every dot is a pair $(m,n)$ where $m$ and $n$ are relatively prime.
If you count them (good luck!), you'll count $6087$ dots.
A little over 1/3 of students last year got this correct. (Keep in mind that there's no penalty for guessing, so even if everyone guessed you'd expect about 1/4 to get it right!)
Overall, about one-third of the students who participated in Round 1 scored 7 or higher, which qualified them to advance to Round 2.
You can find lots of past years' Qualifying Tests on the AMS's website at http://ams.org/wwtbam
And you can find our Math Jam transcripts from previous years' contests on the AoPS website (click on "Math Jams" in the "Online School" menu).
A reminder: if your school would like to participate (and it's free! and your school gets an AoPS coupon just for signing up!), a teacher at your school should do one of the following:
1. Go to https://wwtbam.mobius.net/instructor/ and fill out the registration form.
2. Send an email to paoffice@ams.org with the subject line "WWTBAM Championship".
At this point, Mike and I can take questions about the contest, if you have any.
Is there a limit for how many students can compete from one school?
No
No, as long as all the students take it at the same time, of course.
Can UK students apply?
Yes, but I believe the UK procedures are slightly different.
Yes, but the same in Rounds 1 and 2
You'll probably want to write to paoffice@ams.org for more info.
has 2019 already started?
Not quite. It starts Monday.
is it possible for individual students to sign up(without a school)?
No. You have to sign up via a school.
If the student take it this year, can the student take it next year?
Yes.
can homeschool students apply
Yes, but your teacher or homeschooling parent should apply.
What are the prizes from 2nd place to 10th place???
I'm not sure, but the trip to Denver is included.
could any of you clarify whether we can register after Sep. 9th? i.e. any day up to Sep. 26 for this year?
It starts monday. What if the school hasnt signed up yet? Is there a way to start it like next week?
I believe you can register right up to the end of the Round 1 period.
Yes, Dave is absolutely right.
I'd probably register as soon as possible though (you don't have to take the contest the day you register), just in case.
Can you register now?
Yes, the website is open now.
Is the second round the same format as the first?
Yes, except it's short answer instead of multiple choice.
And harder questions.
Can private coaching institutes like Russian School of Math register?
I don't believe so, but I'm not sure. I'll defer to Mike on this.
Send paoffice@ams.org some details about the school and we'll decide.
To go back to the question about registering in the UK, here's the website: https://goodthinkingsociety.org/who-wants-to-be-a-mathematician-is-back-2/
Can you take the exam at other schools?
Can my school register when I’ll be the only one doing it?
Other schools: I don't think so, but you can write to the AMS and explain your situation.
There's no minimum per school. You can register even if only 1 student is participating.
And to reiterate: the contest is free!
What happens if the teacher won`t sign up like in my area.
Can any student attending a school take it if their school registers?
At other schools, yes.
Any student: yes.
when is the deadline?
September 26 is the end of Round 1.
I’m in middle school i can still participate correct?
Yes.
Can a math circle register?
Yes.
The questions are starting to get really specific, so I think we'll end the general Q&A here.
If you still have questions, you can visit the website at http://www.ams.org/wwtbam, or write to paoffice@ams.org
Please join us again for a discussion of Qualifying Round 1 on Monday, September 30, at 7:30 PM Eastern / 4:30 PM Pacific. We'll go through all 10 problems from Round 1. And there will be a Qualifying Round 2 discussion on Monday, October 14, after Round 2 concludes.
Thanks for participating tonight, and good luck on WWTBAM!
Yes, nice to chat with you. Good luck, everyone!
Goodnight everyone. Thank you!
Good luck everyone!
thank you again! but how can i share this information (ie this chat) with my math club officers?
We'll be posting the transcript of the session on the AoPS website later this evening.
You'll find it at https://artofproblemsolving.com/school/mathjams-transcripts
when will transcript be open
Hopefully by 9 PM (Eastern) tonight.
A huge thank you to Dave, Mike, Bill, and everyone who attended the math jam tonight.
This room will be closing shortly!
Thanks!
Goodnight!
good night and Thanks!
Thank you
Goodnight
Bye
Thank you!
Thanks!
Thanks for taking your time to do this mathjam!
thx
bye
Tyty
Wonderful thank you!
Thanks you!
Bye!
Thanks so much!
thank you
Copyright © 2024 AoPS Incorporated. This page is copyrighted material. You can view and print this page for your own use, but you cannot share the contents of this file with others.