Multi-Digit Multiplication

Lesson 3

Math

Unit 2

4th Grade

Lesson 3 of 18

Objective


Solve multiplicative comparison problems with an unknown multiplier. Interpret a multiplication equation as a comparison.

Common Core Standards


Core Standards

  • 4.OA.A.1 — Interpret a multiplication equation as a comparison, e.g., interpret 35 = 5 × 7 as a statement that 35 is 5 times as many as 7 and 7 times as many as 5. Represent verbal statements of multiplicative comparisons as multiplication equations.
  • 4.OA.A.2 — Multiply or divide to solve word problems involving multiplicative comparison, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem, distinguishing multiplicative comparison from additive comparison.

Foundational Standards

  • 3.OA.A.1
  • 3.OA.A.3

Criteria for Success


  1. Solve multiplicative comparison word problems with an unknown multiplier (MP.4). 
  2. Write an equation to represent a multiplicative comparison word problem with an unknown multiplier, using a letter to represent the unknown (MP.2).
  3. Write an equation to represent a non-contextual verbal statement of multiplicative comparison (MP.2). 

Tips for Teachers


  • Similar to Lessons 1 and 2, while the primary focus of this lesson is on multiplicative comparison problems with an unknown multiplier, the Problem Set and Extra Practice Problems will also spiral in comparison problems of varieties they saw in Lessons 1 and 2. This encourages students to make sense of the mathematics (MP.1).
Fishtank Plus

Unlock features to optimize your prep time, plan engaging lessons, and monitor student progress.

Anchor Tasks

25-30 minutes


Problem 1

Mrs. Ingall wants to place students’ pencil boxes on her bookshelf for the start of the school year.  We know her bookshelf is 24 inches long. Each pencil box is 2 inches wide. 

 

a.   How many pencil boxes can she line up along the bookshelf?

b.   How can you use your answer from Part (a) to determine how many times as long the bookshelf is than a pencil box?

Guiding Questions

Create a free account or sign in to access the Guiding Questions for this Anchor Problem.

Student Response

Upgrade to Fishtank Plus to view Sample Response.

Problem 2

Jade has $63. Keith has $9. How many times as much money does Jade have as Keith? Represent the situation as an equation to solve.

Guiding Questions

Create a free account or sign in to access the Guiding Questions for this Anchor Problem.

Student Response

Upgrade to Fishtank Plus to view Sample Response.

References

Achievement First Grade 4, Unit 1, Lesson 7Independent Practice, Question #3

Grade 4, Unit 1, Lesson 7 is made available by Achievement First as a part of their Open Source web portal under a CC BY 4.0 license. Copyright © 1999-2017 Achievement First. Accessed Jan. 8, 2018, 1:51 p.m..

Modified by Fishtank Learning, Inc.

Problem 3

Conner wrote the following equation:

$$6\times8=n$$

Which statement about Conner’s equation is true?

Create a free account or sign in to view multiple choice options

Guiding Questions

Create a free account or sign in to access the Guiding Questions for this Anchor Problem.

Student Response

Upgrade to Fishtank Plus to view Sample Response.

References

Massachusetts Department of Elementary and Secondary Education Spring 2015 Grade 4 Mathematics TestQuestion #20

Spring 2015 Grade 4 Mathematics Test is made available by the Massachusetts Department of Elementary and Secondary Education. © 2017 Commonwealth of Massachusetts. Accessed March 23, 2018, 1:19 p.m..

Problem Set

15-20 minutes


Discussion of Problem Set

  • What are the two correct statements in #3? What made it difficult to choose? Look at #1. What was similar about all three problems? What was different? 
  • What statement did you write for #5? Is there more than one correct answer? What would be an incorrect statement using the terms “times as many”? 
  • What makes the language in #6 tricky? 
  • In #8, many of the computations involved are probably ones you don’t have memorized. What strategies did you use to solve? 
  • In #8, what was similar and different about Parts (b) and (c)? 
  • How did you solve #9? What made this more challenging than other tasks we’ve seen? (Note that #9 is technically a multi-step problem. However, because the computations involved are straightforward and because it provides a nice preview to the work students will do at the end of the unit, it is included here.) 

Target Task

5-10 minutes


Problem 1

A baseball team scored 72 runs for the season. This was 9 times the number of runs scored in the first game. How many runs were scored in the first game? 

Student Response

Upgrade to Fishtank Plus to view Sample Response.

Problem 2

There are 7 grams of sugar in a serving of strawberries. There are 21 grams of sugar in a serving of strawberry ice cream. How many times as much sugar is there in strawberry ice cream compared to strawberries? 

Student Response

Upgrade to Fishtank Plus to view Sample Response.

Problem 3

Write an equation to represent the statement “448 is 32 times as many as 14.” 

Student Response

Upgrade to Fishtank Plus to view Sample Response.

Additional Practice


The Extra Practice Problems can be used as additional practice for homework, during an intervention block, etc. Daily Word Problems and Fluency Activities are aligned to the content of the unit but not necessarily to the lesson objective, therefore feel free to use them anytime during your school day.

Word Problems and Fluency Activities

Word Problems and Fluency Activities

Help students strengthen their application and fluency skills with daily word problem practice and content-aligned fluency activities.

Next

Multiply 10, 100, and 1,000 by one- and two-digit numbers.

Lesson 4
icon/arrow/right/large

Lesson Map

A7CB09C2-D12F-4F55-80DB-37298FF0A765

Topic A: Multiplicative Comparison

Topic B: Multiplication of up to Four-Digit Whole Numbers by One-Digit Whole Numbers

Topic C: Multiplication of Two-Digit Whole Numbers by Two-Digit Whole Numbers

Topic D: Multi-Step Word Problems

Request a Demo

See all of the features of Fishtank in action and begin the conversation about adoption.

Learn more about Fishtank Learning School Adoption.

Contact Information

School Information

What courses are you interested in?

ELA

Math

Are you interested in onboarding professional learning for your teachers and instructional leaders?

Yes

No

Any other information you would like to provide about your school?

We Handle Materials So You Can Focus on Students

We Handle Materials So You Can Focus on Students

We've got you covered with rigorous, relevant, and adaptable math lesson plans for free