Daniel Lemire's blog

, 22 min read

I still don’t have the multiplication tables memorized

28 thoughts on “I still don’t have the multiplication tables memorized”

  1. Peter Turney says:

    I’m with you on several of these items. There are very few things that I deliberately try to memorize. My reasoning is, if I use some fact often enough, eventually I’ll memorize it by sheer use. If I don’t use it often enough, then there’s no point in memorizing it.
    I confess this gets me into trouble in certain social situations. Names of new acquaintances are a problem.

  2. Sudarshan, your wish is granted:

    http://code.google.com/p/lemurbitmapindex/

  3. Sudarshan says:

    On an entirely different note could you please make that C++ code available.
    Thanks

  4. Sylvie says:

    OMG! I’m not the only one who doesn’t know the multiplication table by heart? I feel so much better now.

    1. Hadi says:

      Even though you posted this comment 15 years ago, let me tell you…yes, you are definitely not alone

  5. Dennis Coxe says:

    I do know my multiplication tables and my social security numbers, but everything else? Forget it! That said, I disagree with your statement that schools “should not be to teach specifics.” I understand the point you are trying to make, which is that we should not try to apply a uniform template to judge all children, but there needs to be a structure around learning and that requires teaching specifics.

    1. Tara says:

      Does there need to be a structure around learning? Why? How much? Who or what provides the structure? Who deems it adequate: the learner or the instructor? Does a structure require teaching specifics? Who chooses the specifics? Based on what? It’s very easy to make statements that sound true and beyond debate.

  6. I’m a special education teacher and give support to all kinds of teenagers who have been identified as having some sort of learning disability.

    Of course people can learn how to get around their weaknesses and use their strengths to succeed in life. You obviously have. Congratulations. I mean that sincerely. But, it makes it much more difficult to succeed at school if you can’t learn the specifics that schools expect you to learn.

    I think it’s important to remember that succeeding at school doesn’t necessarily translate into succeeding in life. There’s more to it than that.

    To be honest, I wish my students could remember their times tables because it would make it easier for them to do the higher level math. I see them struggling with algebra because they don’t know their times tables even though they have a calculator at their finger tips.

    PS- my students don’t know their Roman Numerals either 🙂

  7. Dave says:

    I agree with Elona, but based on much less experience. When I was in high school, I tutored elementary school students. It was so frustrating to me that they understood fractions and other upper elementary concepts perfectly but got low grades and math anxiety because they didn’t know the mult. tables well enough to implement and solve problems.

    I think it’s awesome that you’re able to implement and be recognized for your high-level abilities, but I don’t want to see any kids suffer through what I saw if they don’t have to.

    (XIIX is not legal?)

  8. Anon says:

    I’m a PhD student at Berkeley and I happily confess I don’t have it memorized either.

    PS. nor my father’s name

  9. Anonymous says:

    im 15 and still dont know my time tables im good in every other subject but i just cant get this through my head i think if i tell my mom i have a problem she might think im just being lazy

    1. Mae says:

      Do you know them yet…11 years later?

  10. Valerie says:

    How happy am I to read this. I am a 58 year old woman and I have been trying all my life to memorize my times tables without success. In school we had to stand up when we had memorized a table and recite it to the class, it was purgatory for me as I would learn it and as soon as i stood up it would fly out of my head, resulting in class giggles and me being devastated.

  11. Phil says:

    Hi there, I am 30 years old and can’t remember my tables. I can’t remember birthdates either or anything with numbers in them. I can’t even add 56 + 47 in my head but am doing a mechanical engineering degree and getting A’s. I must admit it would be a lot easier if I could somehow understand numbers as it really slows me down when I can’t factorize or do 3(9x). I feel I must have something wrong with me as I forget so quickly but I’m not sure what. It might be some grade of dyscalcula but I do “see” the numbers and can do say 20+ 29.

  12. Donna says:

    I have tried so very hard to remember numbers but my brain always refused to keep a place where they could stay with that being said it is funny that I can remember many things from books that I read ,but it has stopped me from a high school diploma the sad story’s of our education system do not work for learning disability people.I’m not alone Thank you.

    1. Julia B says:

      Learning disability is a strong word to use, because everyone has different disabilities. Some people are pure genius with math, however they are very challenged with social situations. So for them… their memorizing that would benefit them, can be practicing socializing skills, and it would be challenging for them. With that said, the schools are changing slowly in Canada now, because they are understanding after over a hundred years that people are brilliant in different ways. So everyone cannot fit into the old fashioned model. It was a disabled model of teaching everyone. Perhaps with some math teachers they didn’t help with making it fun and easy. Now we can look online and find hundreds of easy tricks. Amazing weird ways over 80% of the people never knew. Procrastination is probably a stumbling block for over 50% of kids these days because of all the exciting video games, online stuff, sports etc..So I say, it’s still important for kids to memorize up to 12x. It will help them with shopping, taxes,building anything etc.. For adults we only can brush up on what’s useful to us. If a person can’t do art. We do not say they have a disability in Art. Same with anything else. The schools will just slowly change the harmful ways/ words they have used in the past. We are all brilliant in different ways. Everyone has challenges. It’s time for everyone to work on their challenges and celebrate are differences. We all make the world Awesome, as we are…

  13. rajeev rcp says:

    Im not alone

  14. Anonymous says:

    I am 21 years old I learned the multiplication table back in my country and when I moved to America everyone used calculators therefor I never exercised my knowledge, before I knew it I was 21 and completely forgot the multiplication table 😓 I felt stupid but reading this honestly made me feel better. I am glad I am not the only one.

  15. Morag says:

    I am 53 and with an accounting degree and an MBA and just scored 20% on a multiplication tables challenge. I have to admit it does really bother me that I can solve business problems but I am slow at mental maths. I have always felt although I am about to be found out as a fraud in my job. Yet I have held senior posts and worked successfully as a consultant. I have decided this year that I am going try to tackle this, an have embarked on brain training and numeracy challenges to see if I can get the times tables to stick finally.

    1. I am slow at mental maths

      Most processors today can execute billions of multiplications per second. I wrote “billions” not “thousands” or “millions”, but “billions”.

      No matter how hard you train, you are never going to get close to the accuracy and speed of a computer. Never.

      1. Cathie Currie says:

        In second grade, I could recall multiplication through 6×6, whereas I struggled recalling multiplication of numbers larger than 6, especially odd-even pairs. Odd-odd was a bit better.

        I saw that the other students could recall all of the combinations at about the same level of ease in learning and recall speed. I realized most people have a contiguous memory matrix up to 12×12, whereas my matrix was 6×6, one-quarter of what seemed to be a ‘usual size’.

        I sort of shrugged, said to myself, “Hmmm . . that isn’t good. But it just means I will need to work harder at solving problems.”

        So yes, my PhD is in social psych, I’m proficient in programming, did a postdoc in epidemiology. At an Ivy. And my high school had recommended I not do college. 😂😂

  16. Roy White says:

    Interesting I am the same (cant remember tables) I also have the same with foreign languages.
    I have tried to learn them and found I can understand the words when spoken, but can’t recover to Speke them.

    Anybody else found this?

  17. Amihai Shapira says:

    My daughter had a hard time learning the multiplication table. So I wrote an android application to help her‚ Each exercise you solve helps you to feed the cute panda. You can get daily reminders to feed the panda (solve exercises) and you get rewarded with trophies upon goals completion. This application helped her to learn the multiplication table without noticing‚ * Currently the application is only for Android phones * https://goo.gl/9QutZx

  18. François says:

    I also have a PhD in math (and an engineering degree), and don’t have the multiplication tables memorized… I can’t remember any number or text. School was a torture regarding my low memorization ability (repeating a grade is no fun). I’m always saying that math is so great because you don’t need to know anything by heart!

  19. sam says:

    I am 43 with Computer Engineering degree and still can’t remember my multiplication table. I tried, in so many ways. I tried using visual aid to associate numbers to answer, after all our brain think about a picture of a tree when someone mention the word “tree” and we don’t visualize the word. I am still trying to find a way to remember those numbers. I think my problem started as a kid when I learned how to figure out the next number on the multiplication table and that was a mistake. so if you ask me 6×6 I would take a minute and think ” I know 6×5 is 30″ and then I would add a 6 to it which makes 36. so since I know how to come up with the next number I never needed to memorize it and I can’t undo it 🙁

  20. Julian Hyde says:

    I’m sure you have them memorized up to 1:

    0 x 0 = 0
    0 x 1 = 0
    1 x 0 = 0
    1 x 1 = 1

    Enough for a computer scientist!

    1. It looks suspiciously like the AND operator.

  21. Kitty says:

    Thank you for sharing, I am 49 and forgot my time tables. I was a Special education teacher. In the past 10 years my psyche has been tramatized by being a widow before age 40, a caregiver to a mom with end stage renal disease at the time, and my Fathers sudden death all in the same 2 year time span, I had to quit teaching, and suddenly felt extra dumb and sa feeling I lost my smart magic, my test taking confidence. I know I have a learning disability but not sure what it is. I have spent my entire life hiding that I forgot about it. I always score 98-99 percentile in school chievement test throughout school. I had a 3.3 gpa without studying or opening a book in college, BSW Minor in Gerontology. I passed all my Praxis and teacher licensure without study or finishoing the exams. My licencens held at the time allowed me to teach General ed k-12, all subjects, and Special Ed, autism, sever profund gifted, adaptive curriculum, ect. I feel like I am getting dementia, I am tryiong to learn Python, and it feels like I am learning mandorin. My short-term memory is shot. I do have ADHD. I take Vyvanse, but I don’t think its optimal dosage. I don’t necessarily want to up the dosage due to my age. When you shared your moment, I cried…I felt connected. Thank you.