About this video
This video compares 7,000 + 900 + 7 with 7,000 + 970 by writing both as numbers and in expanded form. Comparing place by place shows 7,907 is less than 7,970, and the video explains how to remember the less than and greater than symbols.
You'll be able to
- turn an expression like 7,000 + 900 + 7 into a single number.
- compare two numbers place by place using expanded form.
- choose the correct symbol, < or >, to compare two numbers.
Key words
- expanded form
- Writing a number as the sum of the values of its digits, like 7,000 + 900 + 70.
- less than symbol (<)
- A symbol that points to the smaller number, which is on its left.
- greater than symbol (>)
- A symbol that points to the smaller number, which is on its right.
Transcript
Compare the expressions on both sides of the question marks. So on the left-hand side of the question mark, I have 7,907. So, it's 7,000 plus 900 plus 7, which is going to be the same thing as 7,907. Now let's compare that to what we have on the right-hand side of the question mark.
On the right-hand side, we have 7,000 plus 970, which is 7,970. Or if we wanted to expand it out, we could write that as 7,000 plus 900 plus 70, and then we have 0 ones. So if we compare place value by place value, we have 7,000 in either case. So the thousands place is the same.
We have the same number of hundreds. We have 9 hundreds. But here we have no tens, and we have a 7. And here we have no ones, and we have 70. And clearly, 70 is greater than 7. So the number on the right is greater than the number on the left, or the number on the left is less than the number on the right.
I always remember the less than symbol because it points to the smaller number, or either of these symbols point to the smaller number. So this right over here would mean greater than. You have the larger number on the left. This is less than. You have the smaller number on the left.
So we would go with less than. This is less than that.
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