Sal places numbers 842 and 507 into a place value table. Created by Sal Khan.
Want to join the conversation?
- When reading the number what direction should one start at?(2 votes)
- When reading a number, we usually start from the left and move to the right. This is because the leftmost digit represents the largest place value (like hundreds or thousands), and as we move to the right, the place values get smaller (like tens and ones).(1 vote)
- is that correct? yes it is correct its also known as.......................(2=2 and 4=40 and 8=800) and that is true!(1 vote)
- [Instructor] So I have this number here, and what I would you to do is pause this video and tell me for this number, how many hundreds do we have, how many tens, and how many ones? Pause this video and try to think about it. (bell dings) All right, well, we can just look at each of the place values. And we can start in either direction, but let's start on the right side. So if we start on the right, we look at the ones place right over here, and this tells us that we have two ones. So we could write that right over there. And then we go to the next place value. We go one place to the left. We go to the tens place. This tells us how many tens we are dealing with. And this is four tens. So we'd write that like that. And then last but not least, if we go one more place to the left, this is the hundreds place, and so we have eight hundreds. So this number, which is 842, it's the same thing as eight hundreds, plus four tens, plus two ones. Or another way to think about it is you could view it as 800, plus four tens is the same thing as 40, plus two ones is the same thing as two. So these are different ways of representing the same number. Now, what I just did up here, this is known as a place value table, which we will be discussing many times as we start building our understanding of place value. So it's good to know what people are talking about when they say, "Place value table." So let's just do one more example. Let's say that we had the following number. So this number right over here. And let's put that into a place value table as well. So how many hundreds am I dealing with, how many tens, and then how many ones? Pause this video again and see if you can figure that out. Fill out this place value table. All right, well, we can see that this is the number of hundreds, this is the number of tens, 'cause that's the tens place, and this is the number of ones. The ones place, tens place, hundreds place. And so if we start at the left this time, we have five hundreds. We see that right over there. We actually, and this one's an interesting example, we have zero tens. So we'll just put a zero right over there. And we have seven ones, so we put a seven right over there.