Step-by-step plan to take part in our latest Honorary Mental Math Challenge

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May 6 update:

Thanks and congratulations to all 364 participants of the 2022 Honorary Mental Math Challenge and the 2022 Honorary Memory Challenge!

Links to the full results can (finally) be found on the front page of this website.


Please let us know if something is unclear or if you find any mistake or technical problem.

If you’re not sure how this “honorary challenge” is supposed to work overall, please return to the preceding page and check out the questions and answers sections.


[Friendly warning: This page includes a lot of text, many more or less important explanations and several different versions of the same documents. However, everything is organized so that you can quickly identify which sections you need to read and which are not relevant to you. If you already know everything you need to know, feel free to ignore all the paragraphs that don’t apply to you, download your first challenge directly, and start as soon as you’re ready].


If you want to practice in advance:

  • If you’re unfamiliar with them, first make sure to learn about the different rules and events here
  • If you want to practice more before your “real” attempts, you can use some of the sample disciplines on this page. Or you can use those you will find below.
  • You can click here if you want to learn more about how it’s possible to become much, much faster with mental calculations.


If you want to print:

Do you want to answer everything directly on your computer or do you want to print out all the challenges in advance? If you want to print them all in advance, you can scroll down this page, download and print everything you’ll need now if you want. You should probably use the pdf format. Important note: we added way too many pages and too many problems to each document. Unless you’re some kind of world champion, you almost certainly don’t need to print them all. We’ll tell you in advance how many problems appear on each page so that you can decide how many pages you might need to print. Documents are often 5 pages long just in case, but almost everyone will only need the first 1 or 2 pages.


If you want to follow a strict schedule and simulate a real championship:

  • If you want you can simply do one challenge once a while during your lunch break when you have time and e-mail us after you’re done. If you want to be more hardcore about the whole thing, you can plan in advance where and when you will be tested and do everything in one day. If you go for that option, ideally I suggest you block out at least 4 hours in total for the big day, to make sure you have enough time for breaks and correction and so on.
  • And if you really want to simulate a real championship, you can also plan a self-imposed schedule in advance. “1pm – Additions 1st attempt / 1:15 pm – Additions 2nd attempt” and so on. It’s more difficult to start calculating at a predetermined moment than waiting until you’re feeling perfectly relaxed and ready.


About all those different document formats:

For every single document, you will find 2 different versions and 3 different formats. You will find a version with only the questions and a version with both the questions and the answers. Obviously, please make sure that you don’t accidentally use the documents with all the answers when it’s time to test yourself.

You can choose to use either .pdf, .doc or the .xlsx format. The .pdf documents should appear exactly the same no matter what computer or software you’re using. But because I used a lesser-known clone of Excell and Microsoft Word to design all the different challenges, it’s possible that the formatting of .doc and the .xlsx versions won’t appear on your screen exactly as I intended. It will probably be fine, but you might want to check first.

  • .pdf documents are read-only. They’re perfect for printing, but you can’t write directly on them from your computer. You could however choose to just write down your answers on a random sheet of paper or another open document.
  • .doc documents should work like Microsoft word documents. Normally you should be able to open them and write on them without any problem, but I can’t guarantee it 100%.
  • .slsx are like Excell documents. You should also be able to open them and answer directly on them, but I can’t guarantee it 100%.

Just to be clear, we provide many different versions of each document to make sure that everyone will find something that works for them. You certainly don’t need to download them all! Just choose whichever format you prefer and ignore all the others. If you aren’t sure which one you should use, perhaps you could make a quick test or two before you officially start your attempt?


If there’s a problem when you’re trying to download some documents:

If the “download” button isn’t working directly, try using right-click and then “Save link as”. The name of the document with the (untrue) mention “can’t be downloaded securely” might then appear on the bottom-left corner of your screen. Click on the little arrow next to it and then select “keep”.


Friendly reminders about the Advanced, Regular and Beginner sections:

  • If you’re taking part in the Advanced section, you have to calculate everything mentally before writing your answers. Your points won’t be considered valid if you also write down your calculations.
  • If you’re taking part in the Regular section, you face all the same problems as participants in the Advanced section, but you’re allowed to write down all your calculations. Writing down your calculations will of course be simpler if you’re printing and using pen and paper. If that’s not an option, you can do like me and write one sub-result on the first line after the problem before writing the full result on the second line. (For reasons we’ll explain below, you shouldn’t write anything on the third line)
  • If you’re taking part in the Beginner section, the problems you will face will be simpler. And you can of course write down all your calculations. Make sure to click the highlighted correct link to access the right documents.
  • For the optional challenges, as long you make it clear when you’re reporting your results, it’s possible to choose to attempt some optional challenges while calculating everything mentally (Advanced section rules) and some other optional challenges while writing down your calculations (Regular section rules).



– –

How to identify yourself, note down and report your results:

Here is an example of how a participant might identify him or herself and report his or her results:

  • Your name (either your real name or a pseudonym)
  • The city or region of the world where you live (optional)
  • Your age (optional)
  • Advanced or Regular or Beginner section

When it comes to reporting your results, for each event and each attempt, please note your attempted score (how many problems you gave an answer for) and how many good answers you got. For the best result you manage to achieve, also note down your final score including penalties. Remember that the way your final score is calculated for each challenge isn’t always the same. For divisions for example, maybe you answered 15 problems and got 12 right during your first attempt and then you answered 16 problems and got 13 right during your second attempt. Your final score for divisions would be 13 minus a half-a-point penalty for each of your three mistakes. In that case, your division results would be noted as follow: Attempt 1: 12/15. Attempt 2: 13/16. Final score: 11.5

Please read the rules and calculate your results yourself. Do not send pictures.

Here’s an example of how the full results of a participant in the Advanced section could be noted.

  • Additions: Attempt 1: 8/11, Attempt 2: 10/10, Final score: 10
  • Multiplications: Attempt 1: 20/23, Attempt 2: 21/27, Final score: 18.5
  • Divisions: Attempt 1: 20/24, Attempt 2: 16/28, Final score: 18

Comments (optional): “Overall I’m happy considering how long it has been since I last practiced. But I could have done much better with divisions.”

* If it seems like too much trouble to calculate and report all those not always essential details, you can choose to report only your final score for each challenge.

** If you also choose to attempt some optional challenges, the way you will report your results for those will be similar to what you just saw, with a few minor changes in some cases. We will explain the details before you get there.

If your job is to supervise a large number of participants:

If you’re supervising a large number of participants and you want to help make our job easier, please send some easy-to-read charts with all the results. It’s better if you don’t use pdf and you’re instead using some other format that allows us to use the copy/pasting function. It could look something like this:

Or if you prefer to keep things simple, your chart could instead include only the names or pseudonyms and the final scores (best of 2 attempts) and look something like this:

* If some of the participants you’re supervising are taking part in the Advanced section while others are taking part in the Regular or Beginner sections, please either specify that fact after their names, or send different charts for each section.

** If you’re gathering somewhere in a group and you’d like to take a few pictures, we’d be happy to publish some of those along the results : )


If you aren’t printing, you’re answering everything directly on your computer and you want to speed up the correction process:

You should know that every .xlsx and every .doc document includes some not always visible gridlines, some empty boxes where you can write your answers and some other boxes where the correct answers to each problem are written in white (and therefore invisible to you). You can make the gridlines visible or invisible by changing the options in the program you’re using. And you can make the correct answers visible by selecting everything and before changing the text color to black or to some other color. That means you can choose to first write down your own answers and then, when the 5 minutes are up, make all the correct answers appear next to yours. Using this method can considerably speed up the corrections process. If you’re not sure how to do this, this page explains everything in more detail. That’s true for all the main events and all the optional events. The image below shows you where those answers are hidden for different events:

Be careful to note down your answers either immediately to the right of each problem or, when possible, immediately underneath. It’s better to avoid writing in the boxes where the hidden answers happen to be.


Ready to start?


I hope you’re feeling great and I hope you slept well the night before.

Some annoying last few points:

  • DON’T SKIP ANY PROBLEM! For every challenge, you have 5 minutes to try to solve as many problems as you can, starting with the very first. The scoring system will penalize you if you try to skip ahead to the easier-looking problems.
  • If you’re participating in the Advanced section, remember to only write down your final answers. Your results won’t be considered valid if you’re also writing down your calculations.
  • If you want to preserve all your energy for problem-solving, you can choose to wait until you’re done with everything before correcting your sheets.

Ok that’s more than enough rambling for now, let’s start your first challenge.


First challenge – Additions – 5-minute – Two attempts

[If you’re taking part in the Beginner section, please refer to this page for all the documents and instructions you will need.]

You should know this already but just in case: The pdf documents are perfect for printing. Use either the .xlsx or the .doc documents if you’re answering questions directly on your computer. Again use those instructions if you want to speed up the correction process. If you aren’t sure which type of document you should use, please check the more detailed instructions already written above in the “About the different types of documents” section.

Each additions document has 5 pages with 30 additions per page. Most people will have more than enough with just the first page. Some of the fastest participants will get to the second page. Very few or none will need more than that. If you’re printing, don’t print more than what you might need.

First attempt:

Second Attempt:

For each attempt remember to note not just the number of good answers you had but also the number of problems you attempted. Your final score will simply be the number of good answers you managed to get with your best attempt. Additions is the only challenge where mistakes aren’t penalized. The results you will send us should look something like this: Attempt 1: 8/10, Attempt 2: 9/11, Final score: 9


Second challenge – Multiplications – 5-minute – Two attempts

[If you’re taking part in the Beginner section, please refer to this page for all the documents and instructions you will need.]

[Please refer to this page if, like some advanced competitors, you would rather read your multiplications horizontally rather than vertically]

Each multiplications document has 5 pages with 64 multiplications per page. Most people will have more than enough with just the first page. Some of the fastest participants will get to the second page. Very few or none will need more than that. If you’re printing, don’t print more than what you might need.

First attempt:

Second attempt:

For multiplications, for divisions and for most of the optional challenges, your final score will be the number of good answers you got minus half a point for every mistake*. If you got 9 good answers and 5 bad answers, your final score will be 6.5 (9 minus half a point for each mistake). The results you will send us should look something like this: Attempt 1: 9/14, Attempt 2: 7/14, Final score: 6.5

* For every challenge except additions, if you choose to skip some problems, every missing answer will be considered a mistake and penalized accordingly. Of course no penalty will be given for unanswered questions past the last question that was answered.


Third challenge – Divisions – 5-minute – Two attempts

[If you’re taking part in the Beginner section, please refer to this page for all the documents and instructions you will need.]

Each document has 5 pages with 49 divisions per page. Most people will have more than enough with just the first page. Some of the fastest participants will get to the second page. Very few or none will need more than that. If you’re printing, don’t print more than what you might need.

For divisions, when necessary, you need to write a comma or a dot and the correct following 2 decimals. For those 2 decimals past the comma, we’ll accept either the straight non-rounded up or down answer, or when applicable the correctly rounded up or down answer. For example, the complete answer to 149/7 is 21.28571428571… We only want you to write 2 decimals past the dot, so 21.28 would be an acceptable answer and 21.29 (correctly rounded up) would be another acceptable answer. However, 21.27 wouldn’t be considered acceptable because in that case, rounding down wouldn’t make sense. For 155 divided by 7, the more complete result gives us 22.142857… In this case, rounding does not change anything and 22.14 is the only acceptable answer. If the answers provided in the documents below include 3 decimals and not 2, that’s only to help for those cases where rounding up or down might make sense.

First attempt:

Second attempt:

You will calculate your final score the same way you did for multiplications. 1 point for each good answer that you managed during your best attempt. Half a point penalty for each mistake.



[Once again, the challenges above are the only ones that are mandatory to all participants. If you aren’t interested in any of the other optional challenges below, there’s no need for you to keep reading after this point. For the maniacs, we have no less than 5 other optional challenges and one “special event” that you might want to try. Everything you might want to know about those optional challenges is explained below. ]



Important notes about all the different optional challenges:

  • For this honorary challenge and for all future in-person official championships, optional challenges are only presented because they can be fun and because we like to see new records being established or broken. Try them if you enjoy them, ignore them if you don’t. They are all judged separately. None of the results from the optional challenges have any influence whatsoever on the final ranking of a championship.
  • For all the optional challenges, the main scoreboard will be for those who didn’t write down their calculations before arriving at their answers. A second scoreboard will be for those where not everything was calculated mentally and some calculations were written down. If you choose to write down your calculations for some events, please tell us so when you’ll be sending your results.
  • As long as you make your intentions clear to us so that we can compile the results accordingly, you can choose to try some optional challenges while writing down your calculations and try some other optional challenges while calculating everything in your head. Just write the mention “With Regular section rules” next to any score where you chose to write down not just the answers but also your calculation.
  • Just like we’ve done so far, we provide a .pdf, .xlsx and .doc version of each document. And for each a version with the answers hidden and a version with the answers already visible. Just like before, you can use the same trick to speed up the correction process and avoid having to use any of the “Answers” documents.
  • There won’t be any “for beginners” versions of those optional challenges.

Special event: Unpredictable Calculations5-minute – Only one attempt

Our first optional challenge is called “Unpredictable Calculations”. For all kinds of reasons, it operates under different rules than all the others, hence the “special event” designation. It’s inspired by one event faced by the participants of the Des chiffres et des lettres TV show. The problems you will see might look like this one: ((((( 32 x 13) – 46) / 5) + 17) x 4).

  • The exact format will be unpredictable, but they will only include some combination of additions, subtractions, multiplications and divisions.
  • The problems presented can always be solved by simply proceeding from left to right. All the parenthesis are only there to make it clear that you don’t need to bother with any of the rules about the order of operations. As you probably know, those rules state that all the multiplications and divisions are supposed to be done before all the additions and substractions. So 12 – 2 x 5 = 2 and not 50. With parenthesis (12 – 2) x 5 = 50 and not 2. For all the problems you will see in this challenge, you can choose to just mentally ignore the presence of all those parentheses and simply always calculate everything from left to right.
  • 60 problems will be shown in the document. It’s extremely unlikely that you will be able to solve them all in less than 5 minutes, but if you do you can note down your time for bragging right.
  • This particular challenge can only be attempted once.

When you’re ready:

One point for each correct answer. Half a point penalty for each mistake.

Thanks to Marc Larocque for all his work designing this special event!


Important note about the other 5 optional challenges:

Even though those last challenges are all “optional”, they will included in our future in-person championships. We’ve tried to simultaneously allow some participants to attempt some optional challenges more than once while also limiting the amount of time needed to get through everything. Here’s the solution we came up with: You’re allowed a maximum of 5 attempts in total for all optional events, and you can choose to distribute those 5 attempts however you prefer! So you could for example choose to attempt advanced multiplications three times and calendar calculations twice while skipping all the other optional events. Or you could try everything once. Or skip everything.

Some important points about this rule:

  • The attempt you may have done already with the “Unpredictable Calculation” special event doesn’t count. You still have five attempts no matter what.
  • Three attempts is the maximum for any single optional challenge.
  • When you attempt the same optional event more than once, only your best result is counted at the end.
  • You have to decide in advance how you plan to use your 5 attempts. You can’t change your mind depending on your results!
  • The one-minute and five-minute versions of calendar calculations count as just one attempt. So if you decide to use three of your five attempts on this one, you would be able to try the one-minute and five-minute formats three times each.

Of course since this isn’t an official in-person championship, there’s nothing stopping you from trying everything three times over the course of several days. It’s of course completely cool if that’s what you want to do, but please make sure to make a clear distinction between your “official” 5 attempts and your “just for fun” attempts. Please only send results from your “official” attempts. hen you’ll be reporting your results. Results from some of practice attempts can appear in the comment section if you want.


How to note down your results from all the different optional challenges:

Same process as before, except that you have to take into account the different scoring rules in some cases.

Also, if you choose to attempt some challenges while writing down not just the answers but also the sub-calculations, you need to add the mention “with Regular section rules” to those results.

Here are some hypothetical results of someone who attempted Unpredictable calculations and Squaring while calculating everything mentally, and Advanced multiplications and Insane multiplications while writing down the sub-calculations.

  • Unpredictable calculations: 5/8, Final score: 3.5
  • Squaring: Attempt 1: 9/12, Attempt 2: 10/12, Final score: 20
  • Advanced multiplications (with Regular section rules): Attempt 1: 9/10, Attempt 2: 11/12, Final score: 10.5
  • Insane multiplications (with Regular section rules): Attempt 1: 1/1, Final score: 1

* It is once again possible to choose to only report your final score for each challenge.

** If you’re supervising a large number of participants, please compile the results in some easy-to-read charts, using a format that allows us to use the copy-pasting function.


Optional challenge: Advanced Multiplications5-minute

[Please refer to this page if, like some advanced competitors, you would rather read your multiplications horizontally rather than vertically]

Multiplications of a 3-digit number by another 3-digit number. So 872 multiplied by 643 would be a possible example. As many as you can in 5 minutes. 1 point for each correct answer. Half a point penalty for each wrong or missing answer.

First possible attempt:

Second possible attempt:

Third possible attempt:



Optional challenge: Squaring – 5-minute

Squaring as many increasingly large numbers as you can. As many as you can in 5 minutes. First set of 15 problems will be 2-digit (63² for example). Those first few problems will probably be more than enough for most participants. For those who manage to get through all the 2-digit numbers, the next series of 15 problems will be 3-digit (352² for example). All the rest will be 4-digit problems like 6507². 2 points for each 2-digit numbers. 3 points for each 3-digit numbers. 5 points for each 4-digit numbers. Half a point penalty for each wrong or missing answer.

First possible attempt:

Second possible attempt:

Third possible attempt:



Optional challenge: Square Roots – 5-minute

Calculate the square roots of 6-digit numbers. As many as you can in 5 minutes. 1 point for the first correct digit. 2 points for the second. 3 points for the third. 4 points for the fourth. 5 points for the fifth. 6 points for the sixth. 7 points for the seventh. 8 points for the eight. So up to 36 points for a completely correct answer. Less for a partially correct answer. Half a point penalty for a completely wrong or missing answer.

* For the very last digit you wrote down, we’ll accept either the straight non-rounded up or down answer, or when applicable the correctly rounded up or down answer. Just like with divisions.

First possible attempt:

Second possible attempt:

Third possible attempt:



Optional challenge: Calendar Calculations – 1-minute and 5-minute

Calculate the day of the week for any date from the year 1600 to 2099. You will have one 1-minute attempt and one 5-minute attempt. 1 point for each correct answer. Half a point penalty for each wrong or missing answer. To save time you can choose to answer using the numbers 1 to 7 instead of writing down the words “Monday”, “Tuesday” and so on. Depending on your preferences, you can decide in advance whether 1 is Monday or Sunday or Saturday.

1-minute – First possible attempt:

5-minute – First possible attempt:

1-minute – Second possible attempt:

5-minute – Second possible attempt:

1-minute – Third possible attempt:

5-minute – Third possible attempt:


Optional challenge: Insane Multiplications – 5-minute

[Please refer to this page if, like some advanced competitors, you would rather read your multiplications horizontally rather than vertically]

Multiplications of an eight-digit number by another eight-digit number. So something like 79,960,546 multiplied by 25,349,034. As many as you can in 5 minutes. 1 point for each correct answer. Half a point penalty for each wrong or missing answer.

Important warning: A friendly participant just warned us that, for some reason that we don’t quite understand, Excel is rounding up or down the very last digit of every answer. So if the answer is 2 026 922 599 212 564, Excel will tell us the answer is 2 026 922 599 212 560. We’ve also been provided with a way to solve this problem, but unfortunately we don’t currently have the time to prepare some new documents. Sorry for that. In the meantime, whenever needed, please use this online calculator (or some other equally reliable solution) to find out the exact correct answers to the problems you’ve solved.

First possible attempt:

Second possible attempt:

Third possible attempt:


That’s all!

Uselessly repeating myself again:

  • Please send your results to cmsa@canadianmindsports.com before the newly updated deadline of April 11. Please refer to the “How to identify yourself, note down and report your results” section on this page if you’re not sure how to proceed. Please calculate your results yourself, don’t just send pictures. Add some comments for us to publish if you want. Use a pseudonym or just tell us if you don’t want your name to be published.
  • If you’re curious, the honorary results we received in 2020 can be seen here.
  • Cheaters will be kidnapped and mercilessly tortured by agents of the CMSA secret police.
  • Thank you for taking part! You rock.