Section B: Practice Problems Decompose to Subtract
In this section, we practiced subtracting two-digit numbers. We learned that when there are not enough ones to subtract by place, you can decompose 1 ten for 10 ones. We used base-ten blocks and base-ten diagrams to show our thinking.
Problem 1 (Lesson 5)
Find the value of each difference. Show your thinking.
Problem 2 (Lesson 6)
Here is Mai’s work with a subtraction expression.
What subtraction expression does Mai’s diagram show?
What is the value of the expression?
Use Mai’s method to find the value of
Problem 3 (Lesson 7)
Find the value of
Problem 4 (Lesson 8)
Here is how Clare found the value of
Here is how Han found the value of
How are Han’s and Clare’s calculations the same?
How are they different?
Problem 5 (Lesson 9)
Find the value of each expression. Show your thinking.
Problem 6 (Exploration)
Here is Han’s method for finding the value of
Show each step of Han’s work with base-ten blocks.
Explain or show why Han’s method works.
Problem 7 (Exploration)
Here is Jada’s method for finding the value of
Explain why Jada’s method works.
Use Jada’s method to find the value of