Section 1
Repeated Addition
Property
Multiplication of a decimal by a whole number can be represented as repeated addition. The whole number, , tells you how many times to add the decimal, .
In this Grade 5 Pengi Math lesson from Chapter 4, students learn to multiply decimals by whole numbers by interpreting the operation as repeated addition and modeling products with base-ten blocks. They use place value charts to regroup units and connect their visual models to numerical results, building a concrete understanding of decimal multiplication.
Section 1
Repeated Addition
Multiplication of a decimal by a whole number can be represented as repeated addition. The whole number, , tells you how many times to add the decimal, .
Section 2
Representing Decimal Multiplication with Grids and Blocks
Base ten blocks can model decimal multiplication by arranging blocks in rectangular arrays, where the area represents the product.
On hundredths grids, decimal multiplication is shown by creating overlapping shaded regions where the intersection area equals the product: creates a rectangle covering squares out of .
Section 3
Model Decimal Multiplication on a Place Value Chart
To multiply a decimal by a whole number , you can represent the decimal on a place value chart times. Sum the units in each place value, regrouping (bundling) any groups of 10 and moving them to the next larger place value to find the product.
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Section 1
Repeated Addition
Multiplication of a decimal by a whole number can be represented as repeated addition. The whole number, , tells you how many times to add the decimal, .
Section 2
Representing Decimal Multiplication with Grids and Blocks
Base ten blocks can model decimal multiplication by arranging blocks in rectangular arrays, where the area represents the product.
On hundredths grids, decimal multiplication is shown by creating overlapping shaded regions where the intersection area equals the product: creates a rectangle covering squares out of .
Section 3
Model Decimal Multiplication on a Place Value Chart
To multiply a decimal by a whole number , you can represent the decimal on a place value chart times. Sum the units in each place value, regrouping (bundling) any groups of 10 and moving them to the next larger place value to find the product.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter