In this Grade 4 enVision Mathematics lesson from Chapter 4, students learn to multiply 2-digit numbers by multiples of 10 using place-value block arrays and area models to identify partial products. By breaking apart factors and applying the Distributive Property, students solve problems such as 20 × 24 by calculating 20 × 20 and 20 × 4 separately, then adding the partial products. This lesson builds foundational multiplication fluency needed for multi-digit computation throughout the chapter.
Section 1
Step 1: Represent Multiplication with an Area Model
To represent the multiplication of a multiple of 10 by a two-digit number, decompose the two-digit number into its tens and ones. The multiple of 10 becomes one dimension of an area model, and the decomposed tens and ones become the parts of the other dimension.
Section 2
Step 2: Find Partial Products Using the Area Model
For a multiple of 10, , and a two-digit number broken into tens, , and ones, :
Section 3
Step 3: Sum Partial Products for the Total Product
To find the total product, add the partial products together.
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Section 1
Step 1: Represent Multiplication with an Area Model
To represent the multiplication of a multiple of 10 by a two-digit number, decompose the two-digit number into its tens and ones. The multiple of 10 becomes one dimension of an area model, and the decomposed tens and ones become the parts of the other dimension.
Section 2
Step 2: Find Partial Products Using the Area Model
For a multiple of 10, , and a two-digit number broken into tens, , and ones, :
Section 3
Step 3: Sum Partial Products for the Total Product
To find the total product, add the partial products together.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter