If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Main content
Current time:0:00Total duration:4:58

Video transcript

the goal of this video is to essentially write down all the numbers in order from zero to a hundred but I'm gonna do it in an interesting way in a way that maybe will allow us to see some patterns in the numbers themselves so let me just start so I'm gonna start at zero one two three four five six seven eight and nine and instead I don't we know of course that the next number is 10 which I could write down but instead of doing that I'm just going to copy and paste all of this so copy and paste all of that and see what this does for us so if I do that how does that help us well we know the next number is 10 which one way to think about it is it's a 1 followed by a 0 what's the number after that what's 11 which is a 1 followed by 1 what's the number after that was 12 which is a 1 followed by a 2 and then 13 14 15 16 17 18 and 19 well that was pretty neat this next row of numbers as I went from 10 to 19 look just like the first ones so the second number is the same in yellow but then I added a purple one to the front of it and one way to think about it is each of these numbers do the purple one that I added that represents 10 so 11 could be viewed as 10 plus 1 12 could be viewed as 10 plus 2 let's see if this keeps working so let's take another row of numbers so let's take another row my original row and what do I get two after 19 well of course after 19 we get to 20 so 22 zero and then 21 22 23 24 25 26 27 28 29 I think you might start to see the pattern here what are we gonna do for the next row well now we're in the 30s so the first number 30 is 30 plus zero 30 plus 130 plus 2 30 plus 3 which is 33 34 35 36 37 38 39 so just doing that I think you already see the pattern the the number on the right we keep going from 0 1 2 3 4 5 6 7 8 9 and then the number on the left if we're in the 10 if we're between 10 and 19 you always have a 1 if you're between 20 and 29 you always have a 2 here between 30 and 39 you always have a 3 now how can how could I complete this going all the way to 99 and a pretty fast well let's just do that so that's going to be my 40s I haven't written it out yet that's going to be my 50s this is going to be my 60s 60s 70s 80s 80s and then I have my 90s right over here and so this one we already said this is going to be my 40s this is going to be my 50s this is going to be I'm trying to make sure I use all my colors my sixties this is going to be my 70s and then I have my 80s and then of course I have I have my my let me do a color that well I'll reuse the magenta I have my 90s so what if I were to just take this so let me just take this right over here and copy and paste that so copy and then let me paste it so now I have 41 51 61 71 81 and 91 now I can do it over here 42 50 to 60 to 70 to 82 and 92 and I can do it for each of these for each of these now so that's now 40 450 460 470 480 494 and so when I do that we see the full pattern we see the full pattern and I'm almost done I'm almost done filling in my numbers from zero to ninety nine forty nine fifty-nine sixty nine seventy nine eighty nine ninety nine and if we just want to feel good we could throw in we could throw in a hundred a hundred right right over there and you see that the pattern still holds we went from one two three four five six seven eight nine and now we got two ten followed by a zero that was pretty neat