Multiplication and Decomposition Concepts

Mallory Sechler, a fifth-grade teacher, demonstrates how to multiply decimals using partial products. The problem involves calculating how far Jack's sister ran, given she ran 1.4 times the distance Jack ran. Mallory decomposes the numbers into place values, calculates partial products, and adds them to find the final result: Jack's sister ran 3.22 miles.

Who is the teacher presenting the lesson?

• Tom Brown

• Anna Johnson

• Jack Smith

• Mallory Sechler

What is the main mathematical operation used in this lesson?

• Multiplication

• Addition

• Subtraction

• Division

Why is multiplication chosen as the operation in this problem?

• Because Jack's sister ran more miles

• Because Jack ran more miles

• Because Jack's sister ran fewer miles

• Because Jack ran fewer miles

How is the number 2.3 decomposed?

• 3 + 0.2

• 2 + 0.4

• 3 + 0.4

• 2 + 0.3

What is the decomposition of 1.4?

• 1 + 0.3

• 1 + 0.4

• 1 + 0.6

• 1 + 0.5

What is the result of multiplying 2 by 1?

• 1

• 2

• 3

• 4

What is the product of 2 and 0.4?

• 0.9

• 0.8

• 0.7

• 0.6

What is the result of multiplying 0.3 by 1?

• 0.1

• 0.4

• 0.2

• 0.3

What is the product of 0.3 and 0.4?

• 0.10

• 0.11

• 0.13

• 0.12

What is the sum of the partial products 2, 0.8, 0.3, and 0.12?

• 3.22

• 3.12

• 3.32

• 3.42