Lesson 16 Multiply Numbers Larger than 20
Let’s multiply numbers that are larger than 20.
Warm-up Number Talk: Three Times Some Numbers
Find the value of each expression mentally.
Activity 1 4 23, Represented
Problem 1
Here is how Clare and Andre represented
How does each diagram show
? How could we use Clare’s diagram to find the value of
? How could we use Andre’s diagram to find the value of
?
Problem 2
Diego tried different ways to partition or split a diagram to help him find the value of
What do you notice about the numbers in his diagrams?
Which diagram would you use to find the value of
? Explain your reasoning.
Problem 3
Find the value of
Activity 2 Some Fine Products
Problem 1
To find the value of
Describe or show what Mai would do to finish finding the value of
Problem 2
Find the value of each product. Show your reasoning.
Activity 3 Play Close to 100, Multiplication
Play Close to 100, Multiplication with a partner.
Place the cards face down.
Each player draws 4 cards.
Each player chooses 2 cards to complete the expression to make a value as close to 100 as possible. Write the 2 digits and the product.
Player closest to 100 wins.
Play 5 rounds. Player who wins the most rounds wins.
Game 1
Round 1
Round 2
Round 3
Round 4
Round 5
Game 2
Round 1
Round 2
Round 3
Round 4
Round 5
Practice Problem
Problem 1
Find the value of each expression. Explain or show your reasoning.