Section B: Practice Problems Subtract Within 1,000

Section Summary

Details

In this section, we learned algorithms to subtract numbers within 1,000. We also learned that we can choose whether to use an algorithm or another strategy for subtracting based on the numbers.

Subtraction. Five-hundred plus thirty plus eight, minus one-hundred plus fifty plus six, equals three-hundred plus eighty plus two.
step 1
Subtraction. Five-hundred thirty-eight minus one-hundred fifty-six equals two.
step 2
Subtraction. Step two. Five-hundred thirty-eight minus one-hundred fifty-six equals two.
step 3
Subtraction. Five-hundred thirty-eight minus one-hundred fifty-six equals eighty-two.
step 4
Subtraction. Step four. Five-hundred thirty-eight minus one-hundred fifty-six equals three-hundred eighty-two.

Problem 1 (Lesson 8)

Find the value of in a way that makes sense to you.

Problem 2 (Lesson 9)

Here is a subtraction calculation.

Subtraction. Five-hundred plus forty plus five, minus three-hundred plus sixty plus three, equals one-hundred plus eighty plus two.

  1. Explain what the 400 above the 500 means.

  2. Explain what the 140 above the 40 means.

  3. Explain how the calculation works to find .

Problem 3 (Lesson 10)

  1. Write 518 and 346 in expanded form.

  2. Use the expanded form to find the difference of the two numbers.

Problem 4 (Lesson 11)

  1. Use an algorithm of your choice to find the value of .

  2. Use an algorithm of your choice to find the value of .

Problem 5 (Lesson 12)

Use an algorithm of your choice to find the value of each difference.

Problem 6 (Lesson 13)

Use a strategy or algorithm of your choice to find the value of each difference.

Problem 7 (Exploration)

Here is Noah’s way to find the value of .




The answer is .

  1. Explain why Noah’s method works.

  2. Use Noah’s method to calculate .

Problem 8 (Exploration)

  1. Find the value of . Explain or show your reasoning.

  2. How is this problem different from other subtraction problems you have solved?