Learn about Singapore Math: Grade 3a, Unit 1 - part 3 Video

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Learn about Singapore Math: Grade 3a, Unit 1 - part 3

Learn about Singapore Math: Grade 3a, Unit 1 - part 3 Welcome back. Well just now we learned how to say this four digit numbers and let’s just do a little bit of a review so I have written down this number and this was if I just write the digits it’s 5, 9, 9, 8 and we learned how do we say this? Well, this is the thousands place and this is 5000, this is a hundred’s place 5900 this is the tens’ place so that’s 90. Nine tens’ is 90 so 5990 and this is one place just eight so this is 5998 and we also learned how to say this number and how do we say it. Well there are six in the thousands’ place so it is 600 there’s nothing in the hundreds’ place so we just ignored it. There’s a 10 here one tens we could have said six thousand ten two but that’s just as it sound right or that just not how we say numbers in English and then this is a bit of an inconsistent pattern but the six thousand and twelve. So, hopefully we have a sense of that so what am I giving you I want to challenge you a little bit. What I want you to do is count so maybe you want to write the numbers down but I want you to write the numbers down but I want you to write the numbers down and say them out loud from 5998 to 6012. So you now keep going up one, up one until you get to 6012 and it might see and might have to go along way but take my word for it you’re not that far and you could forget how far you are when you do the numbers. So pause now and try it yourself, pause right now and I will now assume that you pause and restart it and I’m going to tell you how to do it and hopefully you figured it out but so let’s see we’re going to start it at 5998, we’re going to keep going up until we get to 6012. Let me do it in with our colors so we start we off at 5998, so what happens when we add one to this to 5998. Well, we’ll just get, we just add one to the ones’ place and so that eight becomes a nine so add one. So we had a 9 there, and so what’s the number that we get. We get 5999. Now this is where it gets interesting we have 5000’s, right 5000 cans, 999 what happens when we add one more, what’s one more than nine. What you want to say is 10. Well, that gets me to ten and then you would have, you know you could say 59910 perhaps you could say that but remember just think about this in terms of filling up marbles. All of a sudden in the ones’ place we have enough marble to fill up a ten can right, so let’s fill up a new ten can, so let’s take all of these marbles and put them into a tin can. So what happens, we could instead of we could take this 10 marbles and we could put it into one ten can. So if I wanted to expand this, how do I write this number? I could write this as 5000 and I’m going to focus on this a lot because this is really interesting what’s happening right in here. This is 5000 + 900 + 90, right nine 10 cans and then I have another 10 can and now I have no more one’s right because I took all of this and I put them into a ten can. I hope I’m not confusing you. So, how many10 cans do we have? Well, we had 9 and we have one more so we have 10, 10 cans so we could write this instead of 5 9 9 10 maybe we could write it as and you could see we’re going to through this several times. We could rewrite this as, we took all of this and we made it into a 10 cans so maybe we could write this as 5 9 10 10 which is here and I think I’ve confused you right because that’s the number of 10 cans we have and then 0 ones left over. But one’s again, we can’t and this is— I’m doing this for a reason I mean this is the thousands place, hundreds’ place, tens’ place, ones’ place. This is a 5000, this is a thousands’ place, hundreds’, tens’, ones’ and the reason why we keep running into the promise is you can’t have 10 as a digit. In each place you could only have a numeral between zero and nine. You can’t have a 10 there. So whenever you have a ten you fill up essentially and you can and so when you have one more ten can but you can have 10 10 cans what is 10, 10 cans fill up. Well that fills up a hundred can, right so we could take this ten, ten cans and fill up a hundred cans so maybe we could write this and then if we fill up a 100 can we had 9 how many 100 cans we have. Well we have 1000 cans now. I’m sure I’m confusing you or this might be obvious to you either way. Let’s just so we could say we have 5000 or 5000 cans, we could say we have 1000 cans but that doesn’t make sense that’s a hundreds’ place and then we now we’d have zero 10 cans so it’s slightly different color and zero one can. So these are let me draw the places because we can’t have a two digit number in a place but I’m just doing this for a reason. So these are our places, we have 5000 cans, ten hundred cans, zero ten cans and zero one can. These are all kind of the same number although none of them are valid right because you can have ten in a place you have to a digit. So what happens if you have ten hundred cans well we can fill out, we can fill up another thousand can because ten hundred cans is equal to a thousand can. So let’s take this ten hundreds and add one to the thousand. So this could be 6000 cans and we took all those ten hundreds so we have no longer any hundred cans, we no longer have any ten cans and we no longer have any one can and now we are fine because in every place we have a numeral between zero and nine and we’ll have some kind of weird two digit number within the place and as you can see the number right after 5999 is not 5 9 9 10 or 5 9 10 0 or 5 10 0 0. These are all bazaar numbers and I apologize if I confuse you. The number right after this 6000 I did all of that work just to go from 5999 to 6000 and hopefully that makes sense to you now because you can’t go from 9 to 10 you’re essentially feeling up a ten bucket but if you fill up another 10 bucket you now have 10 10’s so you could actually fill up another hundred bucket. But if you fill up another hundred bucket, you now have 10 hundred buckets so you fill up another thousand buckets and now you have 6000 buckets and you don’t have any extra marble so you have exactly 6000 marbles. So that was a hard part. So from 5998 to 5999 to 6000 and from here it’s easy. What’s the next number? I don’t even have to do place notation here I think it’s 6001, 6002, 6003, 6004 and I’m going to confuse you by going over all the way but it’s 6005, 6006, 6007, 6008, 6008, 6009, 6010, 6011, 6012 and we are done. So that wasn’t too bad that the important thing to realize is what happens when you go from 5999 to 6000. That extra one doesn’t only fill up a 10 bucket which the 10 bucket start overflowing so you feel a hundred bucket so that fills but then you have 10 hundred bucket so you actually are able to fill up a completely new thousand bucket so actually are able to fill up a completely new thousand bucket. So you have 6000 marbles at that point. So let’s do that again with another set of numbers and now just to save time and maybe because you’re smarter than me we don’t need to the colors anymore. So let’s go from this number, to this number and you might want to try it by yourself before I give you the answer so pause now if you want to. But anyway so what is this number we have nine thousands, nine hundred, eight tens so that’s 80 seven, 9987. What’s the next number we will just keeping commenting there let me use a vibrant color let me see this blue looks nice. So the next number is 9980 we just increment the one we’re just adding at a time 88, 9989 and now what happens, this is interesting. If we want to increase this by one what’s one more than nine, what’s ten but we can’t have a ten here in the one’s place. So we’re essentially adding, we can take all of these here so we’re going to have ten one’s and make a new ten. So essentially we can take add the one that becomes a 10 so we have one more tens’ so that becomes 90. what’s 89 +1= 90 so then we have 9990 and now the next fewer pretty easy 9991, 9992, 9993, and that was arbitrarily switch colors for no reason 9994, 9995, 9996, 9997, 9998, 9999 now what happens well if I add one more I get ten ones’ so I could add another 10 can but if I add another ten can then I have 10, 10’s and I can have 10 to 10’s place so then since you have another hundred right what’s 99 + 1 = 100 but then if I have already have 900 so if I have another hundred I’ll have ten hundreds’. So ten hundreds is a thousands so essentially when I add one more to 999 I essentially get another thousand so I add one to the thousand, so now I have, well now I actually have 10 thousand right, ten thousand s’ right so instead of having a ten in the thousands’ place I actually have a new bucket I have actually now have a one ten thousand bucket. So what happens? So I have— instead of having this big ten in that place and then zero, zero, zero although it’s looking exactly the same. We can’t have a ten in the thousand’s place. So what we do is we say well know we don’t have ten one thousand’s we have one ten thousands, so this is a new bucket, this is a bucket, this is a can size it’s made out of ten thousands. We have one of them and I’ll do it on a new color. We have one of those and then we have no thousands left over, hundreds left over, tens left over or one’s left over. So we have 10 by the way this is said, it’s not said one ten thousand this is red actually not too different in this, it’s red as ten thousand. So hopefully that doesn’t confuse you and you know more than thinking about what happens if we fill up buckets the 9 goes to 10 but you can’t have 10 there so put the one here but then that goes to ten and that goes to ten and you keep going. But let my just finish this, but the important thing is to realize that it’s to see the pattern that what happens when you add one to a bunch of nine’s you essentially go to the next place. And you might want to experiment. You know what to see what happens when you go from the number 97 to the number 102, right? You go 97, 98, 99, and then when you add one more you can have 9010. You can have 99010 so you want to add one more here but what happens you can’t have 10, 10, 0 I think I’m confusing you, if you go to a hundred. All right this is a new place and similarly instead of having ten in the thousands place you go to a new place or the ten thousand’s place you go to a new place or the ten thousands place which is here. So, this is ten thousands that are thousands that’s hundred’s, that’s ten’s, that’s zeros. I think this might be pretty intuitive for you and when you kind of do other labels it might be a little confusing. But anyway I’ll live you there and I’ll see you in the next video.

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Learn about Singapore Math: Grade 3a, Unit 1 - part 3

Welcome back. Well just now we learned how to say this four digit numbers and let’s just do a little bit of a review so I have written down this number and this was if I just write the digits it’s 5, 9, 9, 8 and we learned how do we say this? Well, this is the thousands place and this is 5000, this is a hundred’s place 5900 this is the tens’ place so that’s 90. Nine tens’ is 90 so 5990 and this is one place just eight so this is 5998 and we also learned how to say this number and how do we say it.

Well there are six in the thousands’ place so it is 600 there’s nothing in the hundreds’ place so we just ignored it. There’s a 10 here one tens we could have said six thousand ten two but that’s just as it sound right or that just not how we say numbers in English and then this is a bit of an inconsistent pattern but the six thousand and twelve.

So, hopefully we have a sense of that so what am I giving you I want to challenge you a little bit. What I want you to do is count so maybe you want to write the numbers down but I want you to write the numbers down but I want you to write the numbers down and say them out loud from 5998 to 6012. So you now keep going up one, up one until you get to 6012 and it might see and might have to go along way but take my word for it you’re not that far and you could forget how far you are when you do the numbers.

So pause now and try it yourself, pause right now and I will now assume that you pause and restart it and I’m going to tell you how to do it and hopefully you figured it out but so let’s see we’re going to start it at 5998, we’re going to keep going up until we get to 6012.

Let me do it in with our colors so we start we off at 5998, so what happens when we add one to this to 5998. Well, we’ll just get, we just add one to the ones’ place and so that eight becomes a nine so add one. So we had a 9 there, and so what’s the number that we get. We get 5999. Now this is where it gets interesting we have 5000’s, right 5000 cans, 999 what happens when we add one more, what’s one more than nine.

What you want to say is 10. Well, that gets me to ten and then you would have, you know you could say 59910 perhaps you could say that but remember just think about this in terms of filling up marbles. All of a sudden in the ones’ place we have enough marble to fill up a ten can right, so let’s fill up a new ten can, so let’s take all of these marbles and put them into a tin can.

So what happens, we could instead of we could take this 10 marbles and we could put it into one ten can. So if I wanted to expand this, how do I write this number? I could write this as 5000 and I’m going to focus on this a lot because this is really interesting what’s happening right in here. This is 5000 + 900 + 90, right nine 10 cans and then I have another 10 can and now I have no more one’s right because I took all of this and I put them into a ten can. I hope I’m not confusing you.

So, how many10 cans do we have? Well, we had 9 and we have one more so we have 10, 10 cans so we could write this instead of 5 9 9 10 maybe we could write it as and you could see we’re going to through this several times. We could rewrite this as, we took all of this and we made it into a 10 cans so maybe we could write this as 5 9 10 10 which is here and I think I’ve confused you right because that’s the number of 10 cans we have and then 0 ones left over.

But one’s again, we can’t and this is— I’m doing this for a reason I mean this is the thousands place, hundreds’ place, tens’ place, ones’ place. This is a 5000, this is a thousands’ place, hundreds’, tens’, ones’ and the reason why we keep running into the promise is you can’t have 10 as a digit. In each place you could only have a numeral between zero and nine.

You can’t have a 10 there. So whenever you have a ten you fill up essentially and you can and so when you have one more ten can but you can have 10 10 cans what is 10, 10 cans fill up. Well that fills up a hundred can, right so we could take this ten, ten cans and fill up a hundred cans so maybe we could write this and then if we fill up a 100 can we had 9 how many 100 cans we have.

Well we have 1000 cans now. I’m sure I’m confusing you or this might be obvious to you either way. Let’s just so we could say we have 5000 or 5000 cans, we could say we have 1000 cans but that doesn’t make sense that’s a hundreds’ place and then we now we’d have zero 10 cans so it’s slightly different color and zero one can. So these are let me draw the places because we can’t have a two digit number in a place but I’m just doing this for a reason.

So these are our places, we have 5000 cans, ten hundred cans, zero ten cans and zero one can. These are all kind of the same number although none of them are valid right because you can have ten in a place you have to a digit. So what happens if you have ten hundred cans well we can fill out, we can fill up another thousand can because ten hundred cans is equal to a thousand can.

So let’s take this ten hundreds and add one to the thousand. So this could be 6000 cans and we took all those ten hundreds so we have no longer any hundred cans, we no longer have any ten cans and we no longer have any one can and now we are fine because in every place we have a numeral between zero and nine and we’ll have some kind of weird two digit number within the place and as you can see the number right after 5999 is not 5 9 9 10 or 5 9 10 0 or 5 10 0 0.

These are all bazaar numbers and I apologize if I confuse you. The number right after this 6000 I did all of that work just to go from 5999 to 6000 and hopefully that makes sense to you now because you can’t go from 9 to 10 you’re essentially feeling up a ten bucket but if you fill up another 10 bucket you now have 10 10’s so you could actually fill up another hundred bucket.

But if you fill up another hundred bucket, you now have 10 hundred buckets so you fill up another thousand buckets and now you have 6000 buckets and you don’t have any extra marble so you have exactly 6000 marbles. So that was a hard part. So from 5998 to 5999 to 6000 and from here it’s easy.

What’s the next number? I don’t even have to do place notation here I think it’s 6001, 6002, 6003, 6004 and I’m going to confuse you by going over all the way but it’s 6005, 6006, 6007, 6008, 6008, 6009, 6010, 6011, 6012 and we are done. So that wasn’t too bad that the important thing to realize is what happens when you go from 5999 to 6000.

That extra one doesn’t only fill up a 10 bucket which the 10 bucket start overflowing so you feel a hundred bucket so that fills but then you have 10 hundred bucket so you actually are able to fill up a completely new thousand bucket so actually are able to fill up a completely new thousand bucket. So you have 6000 marbles at that point.

So let’s do that again with another set of numbers and now just to save time and maybe because you’re smarter than me we don’t need to the colors anymore. So let’s go from this number, to this number and you might want to try it by yourself before I give you the answer so pause now if you want to.

But anyway so what is this number we have nine thousands, nine hundred, eight tens so that’s 80 seven, 9987. What’s the next number we will just keeping commenting there let me use a vibrant color let me see this blue looks nice. So the next number is 9980 we just increment the one we’re just adding at a time 88, 9989 and now what happens, this is interesting. If we want to increase this by one what’s one more than nine, what’s ten but we can’t have a ten here in the one’s place. So we’re essentially adding, we can take all of these here so we’re going to have ten one’s and make a new ten.

So essentially we can take add the one that becomes a 10 so we have one more tens’ so that becomes 90. what’s 89 +1= 90 so then we have 9990 and now the next fewer pretty easy 9991, 9992, 9993, and that was arbitrarily switch colors for no reason 9994, 9995, 9996, 9997, 9998, 9999 now what happens well if I add one more I get ten ones’ so I could add another 10 can but if I add another ten can then I have 10, 10’s and I can have 10 to 10’s place so then since you have another hundred right what’s 99 + 1 = 100 but then if I have already have 900 so if I have another hundred I’ll have ten hundreds’.

So ten hundreds is a thousands so essentially when I add one more to 999 I essentially get another thousand so I add one to the thousand, so now I have, well now I actually have 10 thousand right, ten thousand s’ right so instead of having a ten in the thousands’ place I actually have a new bucket I have actually now have a one ten thousand bucket. So what happens? So I have— instead of having this big ten in that place and then zero, zero, zero although it’s looking exactly the same. We can’t have a ten in the thousand’s place.

So what we do is we say well know we don’t have ten one thousand’s we have one ten thousands, so this is a new bucket, this is a bucket, this is a can size it’s made out of ten thousands. We have one of them and I’ll do it on a new color. We have one of those and then we have no thousands left over, hundreds left over, tens left over or one’s left over. So we have 10 by the way this is said, it’s not said one ten thousand this is red actually not too different in this, it’s red as ten thousand.

So hopefully that doesn’t confuse you and you know more than thinking about what happens if we fill up buckets the 9 goes to 10 but you can’t have 10 there so put the one here but then that goes to ten and that goes to ten and you keep going. But let my just finish this, but the important thing is to realize that it’s to see the pattern that what happens when you add one to a bunch of nine’s you essentially go to the next place.

And you might want to experiment. You know what to see what happens when you go from the number 97 to the number 102, right? You go 97, 98, 99, and then when you add one more you can have 9010. You can have 99010 so you want to add one more here but what happens you can’t have 10, 10, 0 I think I’m confusing you, if you go to a hundred. All right this is a new place and similarly instead of having ten in the thousands place you go to a new place or the ten thousand’s place you go to a new place or the ten thousands place which is here.

So, this is ten thousands that are thousands that’s hundred’s, that’s ten’s, that’s zeros. I think this might be pretty intuitive for you and when you kind of do other labels it might be a little confusing. But anyway I’ll live you there and I’ll see you in the next video.

Transcription by: Scribe4you Transcription Services