Comparing Numbers

Speaker: Teacher - Hello, Charlotte.

Speaker: Student – Hello.

On-screen: [Mathematical problem:

  1. 486 > 482
  2. 297 > 205
  3. 758 > 3,624.]

Speaker: Teacher - Thanks for meeting with me today to talk about this math problem. I want to learn more about your thinking about this problem. So, I’m wondering if you can tell me what did you do first.

Speaker: Student – I looked at four eighty-six and four eighty-two.

Speaker: Teacher - OK, and what did you find?

Speaker: Student – That four eighty-six is greater than four eighty-two.

Speaker: Teacher - How did you know that?

Speaker: Student – Because six is bigger than two.

Speaker: Teacher - Oh, six is bigger than two.  Are those the digits you looked at first when you started the problem?

Speaker: Student – Um, no. I started with the fours.

Speaker: Teacher - Oh, you started with the fours. Can you point to them?

Speaker: Student – Uh huh. There and there.

Speaker: Teacher - OK, so what did you notice about the…the fours?

Speaker: Student – They are the same number.

Speaker: Teacher - OK, so you noticed that the fours are the same. What is the next thing you did after that?

Speaker: Student – I looked at the eights.

Speaker: Teacher - Can you point to them?

Speaker: Student – Uh huh. There.

Speaker: Teacher - And what did you notice about the eights?

Speaker: Student – They are the same number.

Speaker: Teacher - OK, so first you noticed that the fours are the same, and then you noticed that the eights are the same. What is the very next thing you did after that?

Speaker: Student – I looked at the six and the two.

Speaker: Teacher - Alright, and what did you notice?

Speaker: Student – Six is bigger than two.

Speaker: Teacher - Six is bigger than two. And so what does that tell you about the problem?

Speaker: Student – It tells me that four eighty-six is greater than four eighty-two.

Speaker: Teacher - OK, thank you. Now can you tell me about the next problem?

Speaker: Student – Sure.

Speaker: Teacher - OK, what did you do first?

Speaker: Student – I looked at two ninety-seven and two zero-five.

Speaker: Teacher - And what did you see?

Speaker: Student – Two ninety-seven is greater than two zero-five.

Speaker: Teacher - How did you know?

Speaker: Student – Because nine is bigger than zero.

Speaker: Teacher - OK, I think I understand. When you first looked at two ninety-seven and two zero-five, what did you look at first?

Speaker: Student – I looked at the twos.

Speaker: Teacher - And what did you notice about them?

Speaker: Student – They are the same number.

Speaker: Teacher - Alright, and what does that tell you?

Speaker: Student – It tells you that you have to keep going.

Speaker: Teacher - You keep going where?

Speaker: Student – To the next number.

Speaker: Teacher - Uh huh, but which number?

Speaker: Student – The number to the right.

Speaker: Teacher - Oh, OK; so after you looked at the twos, what did you look at next?

Speaker: Student – I looked at the nine and the zero.

Speaker: Teacher - And what did you notice?

Speaker: Student – I saw that nine is bigger than the zero.

Speaker: Teacher - And, what did that tell you?

Speaker: Student – It tells you that two ninety-seven is greater than two zero-five.

Speaker: Teacher - OK, I’m really learning a lot. Can you tell me about the last problem?

Speaker: Student – Sure, seven fifty-eight is greater than three thousand six-twenty four.

Speaker: Teacher - How did you know that?

Speaker: Student – Because seven is bigger than three.

Speaker: Teacher - When you first looked at this problem, what was the very first thing you looked at?

Speaker: Student – I looked at the seven and the three.

Speaker: Teacher - And what did you see?

Speaker: Student – I saw that seven is bigger than three.

Speaker: Teacher - Alright, and that makes seven fifty-eight greater than three thousand six twenty-four?

Speaker: Student – Yes.

Speaker: Teacher - Did you look at any other digits here?

Speaker: Student – Nope.

Speaker: Teacher - Why don’t you have to compare the five and the six after you compare the seven and the three?

Speaker: Student – Because once you compare the first two numbers, then you’re done. You know which one is bigger.

Speaker: Teacher - OK, I hear you. Now I’m going to give you another problem, OK?

Speaker: Student – OK.

On-screen: [Mathematical problem:

  1. 486 > 482
  2. 297 > 205
  3. 758 > 3,624

In right column, it has 62 < 225.]

Speaker: Teacher - OK, what about this problem?

Speaker: Student – Sixty-two is less than two twenty-five.

Speaker: Teacher - Alright, and how did you know that?

Speaker: Student – Because two twenty-five is more than a hundred, and so that’s bigger.

Speaker: Teacher - OK, I think I understand. Could I ask you another question?

Speaker: Student – Sure.

Speaker: Teacher - What about this problem?

On-screen: [Mathematical problem:

  1. 486>482
  2. 297>205
  3. 758>3,624

In right column, it has 62 < 225 and 534 > 2,786.]

Speaker: Student – Um, there. Five thirty-four is greater than two thousand seven eighty-six.

Speaker: Teacher - Five thirty-four is greater?

Speaker: Student – Yes.

Speaker: Teacher - How did you know?

Speaker: Student – Because five is bigger than two.

Speaker: Teacher - It looks like you always start on this side when comparing numbers. Is this right?

On-screen: [Mathematical problem:

  1. 486>482
  2. 297>205
  3. 758>3,624

In right column, it has 62 < 225 and →534 > 2,786.]

Speaker: Student – Yes, when the numbers are big.

Speaker: Teacher - How do you know if a number is big?

Speaker: Student – Well, if it is bigger than a hundred.

Speaker: Teacher - OK, so just a few more questions. I’m wondering—have you ever heard about ones, tens, hundreds, and thousands?

Speaker: Student – Yes.

Speaker: Teacher - OK, in this number here, which is the ones place?

On-screen: [Mathematical problem:

  1. 486>482
  2. 297>205
  3. 758>3,624

In right column, it has 62 < 225 and →534 > 2,786.]

Speaker: Student – The four.

Speaker: Teacher - And what does that four mean?

Speaker: Student – It’s just a four.

Speaker: Teacher - OK, and which is the tens place?

Speaker: Student – The three.

Speaker: Teacher - And what does that three mean?

Speaker: Student – It’s just three.

Speaker: Teacher - OK, and which is the hundreds place?

Speaker: Student – The five.

Speaker: Teacher - And what does that mean?

Speaker: Student – It’s just five.

Speaker: Teacher - And, which is the thousands place?

Speaker: Student – There is no thousands place.

Speaker: Teacher - Ah, OK. In this number here, which is the thousands place?

On-screen: [Mathematical problem:

  1. 486>482
  2. 297>205
  3. 758>3,624

In right column, it has 62 < 225 and →534 > 2,786.]

Speaker: Student – The two.

Speaker: Teacher - And the hundreds place?

Speaker: Student – The seven.

Speaker: Teacher - And the tens place?

Speaker: Student – The eight.

Speaker: Teacher - And the ones place?

Speaker: Student – The six.

Speaker: Teacher - OK, thank you so much! I learned a lot from our conversation about this.

End of Comparing Numbers video.

Video duration: 8:19