Unit 5, Lesson 19
Use Properties to Multiply Decimals
Grade 5
Warm-up
Find the value of each expression mentally.
Activity 1
Your teacher will give you a set of cards that show multiplication expressions.
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Sort the cards into 2 categories of your choosing. Be ready to explain the meaning of your categories.
Then sort the cards into 2 categories in a different way. Be ready to explain the meaning of your new categories. (Pause for teacher directions.)
- Find Cards A, B, and C. Group each expression with the other expressions that have the same value. Be ready to explain your reasoning.
- Choose 1 expression from each group. Find the value of the expressions on Cards A, B, and C.
- Write at least 1 more expression that has the same value as each expression on Cards A, B, and C.
Activity 2
Find the value of each expression. Explain or show your reasoning.
Activity 3
Find the value of each expression.