National Mental Math Championship

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Important note: This page hasn’t been edited since our last championship in September 2018. Many changes will probably be made before our 2019 championship, so don’t please don’t assume that what you’re reading here is up to date. Chances are that we will keep the same basic format but add one optional challenge with more advanced calculations.


The National Math Championship will start Saturday September 15 at 1:30pm in Montreal and Toronto and at 9:30am in Vancouver. It will last for about 3 hours. Click here for information about the cost and the venues.

Competitors will be tested on their ability to solve as many additions, multiplications and divisions as possible during a series brief 5 minutes exercises. Beginners will be allowed to write their calculations on the page, but the other competitors will have to do everything mentally and only write down their answers.

Click here for some sample disciplines and training tools.

Click here to learn more about how to become crazy fast with mental calculations

The first challenge will be 60 additions of ten 2-digit numbers like 36+44+78+14+97+32+28+81+96+25. The second challenge will be 100 multiplications of two 2-digit numbers like 47 multiplied by 82. The third and last challenge will be 100 divisions of a 3-digit number by a 1-digit number between 2 and 9. So 732 divided by 6 would be a possible example. For each challenge competitors will have 2 attempts separated by a 15 minutes break and only the best results will count at the end. It will be nearly impossible to solve everything in 5 minutes, but it might be possible to solve more than the person sitting next to you.

Two additional math-related challenges will be offered, but they will be completely optional and won’t officially be part of the championship. Only the previously described three challenges will determine who win the titles and the prizes. The other two challenges will be just about fun and bragging rights. The first one of those optional challenges will be happening only in Montreal and it will consist in a short onstage presentation in front of the speedcubers either at the end of their championship. Competitors who agree to take part will show off their skills by quickly answering orally progressively more difficult math questions. The very last optional challenge will be calendar calculations. Can you quickly tell me what day of the week was October 23, 1743? At the very end of the mental math championship, at least one person will be establishing a national record by answering as many of those questions as possible in 1 minute. To save time you can answer using the numbers 1 to 7 instead of writing down the words “monday”, “tuesday” and so on. We can ask about any day from the 17th century up to today.

Click here for an article in French by national mental math champion Jean Béland explaining how you can learn to do those calculations.

Overall scoring rules

For each of the three official challenges each contestant will be awarded a score that can range from 0 to 100. Those three scores will be added at the end and whoever get the most points wins. We’ll present two different scoreboards for beginners and other competitors. Non-Canadian citizens can compete in the Regular section and show everyone who’s boss, but they can’t become the official winner of the championship.

In each challenge the person who obtained the very best score will automatically have a score of 100. Other contestants will have their score calculated by taking the number of good answers they obtained and by dividing that number by the number of good answers obtained by the best competitor and by multiplying the result by 100. So if the best performance in the division challenge was 50 good answers and you obtained 40 good answers, your official score for that challenge will be 80 (40 divided by 50 and multiplied by 100).

  • For additions we simply add up the number of good answers. All the questions presented are about equally difficult.
  • For multiplications and divisions we also add up the number of good answers, but half a point will be subtracted for every wrong or missing answer. This is to avoid giving an incentive to skip the most apparently difficult questions. No penalty will be given for unanswered questions past the last question that was answered.
  • For divisions, when necessary, you need to write a comma and the correct following 2 digits. For those 2 digits 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 answer to 149/7 is 21.28571428571… but we only want you to write 2 digits past the comma. So 21.28 is an acceptable answer and 21.29 (correctly rounded up) is another acceptable answer. However, 21.27 wouldn’t be considered acceptable because in that case rounding down would be incorrect.

Competitors are asked to write clearly to facilitate the correction. All the numbers used will have been generated randomly by a specially designed Excel document.

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