Lesson 9 Compare Numbers on the Number Line

    • Let’s compare numbers on the number line.

Warm-up Estimation Exploration: Hundreds

What number could this be?

Number line. Scale 300 to 400. Point plotted between 300 and 400.
  1. Record an estimate that is:

    too low

    about right

    too high

  2. Record an estimate that is:

    too low

    about right

    too high

Activity 1 Compare Comparisons

Each student compared 371 and 317, but represented their thinking in different ways.

Diego

Base-ten diagram. 3 hundreds. 7 tens. 1 one.
  • I see 3 hundreds for each number. 

  • 317 only has 1 ten, but 371 has 7 tens.

Clare

  • Each has 3 hundreds.

  • 371 has 7 tens, but 317 only has 1 ten.

Jada

Number line. Scale 300 to 400 by tens. 11 evenly spaced tick marks. First tick mark, 300. Last tick mark, 400. Points plotted at 317 and 371.
  • I can see that 371 is farther to the right on my number line, so I know it is greater than 317.

  1. What is the same and different about these students’ representations?

    Discuss with a partner.

  2. Try Jada’s way.

    Estimate the location of 483 and 443 on the number line. Mark each number with a point. Label the point with the number it represents.

    Number line. Scale 400 to 500 by tens. 11 evenly spaced tick marks. First tick mark, 400. Last tick mark, 500. All tick marks labeled.
  3. Use , , or to compare 483 and 443.

Activity 2 Compare in Different Ways

Problem 1

  1. Locate and label 420 and 590 on the number line. 

    Number line. Scale 400 to 600. 21 evenly spaced tick marks. First tick mark, 400. Eleventh tick mark, 500. Last tick mark, 600.
  2. Use , , and to compare 420 and 590.

Problem 2

  1. Estimate the location of 378 and 387 on the number line. Mark each number with a point. Label the point with the number it represents. 

    Number line. Scale 300 to 400 by tens. 11 evenly spaced tick marks. First tick mark, 300. Last tick mark, 400. All tick marks labeled.
  2. Use , , and to compare 378 and 387.

Problem 3

  1. Diego and Jada compared 2 numbers. Use their work to figure out what numbers they compared. Then use , , and to compare the numbers.

    Base-ten diagram. 4 hundreds. 3 tens. 2 ones.
    Base-ten diagram.
    Number line. Scale 400 to 500 by tens. First tick mark, 400. Last tick mark, 500. One point plotted between 420 and 430 and between 430 and 440.
  2. Which representation was most helpful to compare the numbers? Why?

Practice Problem

Problem 1

  1. Estimate the location of 247 and 274 on the number line. Mark each number with a point. Label the point with the number it represents.

     Number line. Scale 240 to 280 by tens. First tick mark, 240. Last tick mark, 280.
  2. Use , , or to compare 247 and 274. Explain your reasoning.