Multiplication and Division of Decimals

Lesson 16

Math

Unit 6

5th Grade

Lesson 16 of 24

Objective


Divide with decimals in all cases, reasoning about the placement of the decimal point.

Common Core Standards


Core Standards

  • 5.NBT.B.7 — Add, subtract, multiply, and divide decimals to hundredths, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used.

Foundational Standards

  • 5.NBT.A.1
  • 5.NBT.A.2
  • 5.NBT.B.6
  • 5.NF.B.3

Criteria for Success


  1. Deduce the general pattern about the placement of the decimal point when dividing decimals, namely that when the decimal point in the divisor is moved to make a whole number, the decimal point in the dividend should be moved the same number of places (MP.8).
  2. Divide decimals in all cases.
Fishtank Plus

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

Anchor Tasks

25-30 minutes


Problem 1

a.   Which of the following expressions are equivalent to 1.33 ÷ 0.7?

  1. 0.133 ÷ 0.07
  2. 1.33 ÷ 0.07
  3. 0.133 ÷ 0.7
  4. 13.3 ÷ 0.7
  5. 1.33 ÷ 7
  6. 13.3 ÷ 7
  7. 13.3 ÷ 70
  8. 133 ÷ 70

b.   What do you notice about the equivalent expressions in Part (a)? What do you wonder?

c.   Use one of the expressions you chose in Part (a) to find the quotient 1.33 ÷ 0.7.

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

Solve. Show or explain your work.

a.   51 ÷ 6

b.   45.2 ÷ 5

c.   3.7 ÷ 20

d.   14.04 ÷ 52

e.   0.9 ÷ 0.25

f.   27.54 ÷ 3.4

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 Set

15-20 minutes


Discussion of Problem Set

  • Which division expression was equivalent to the one given in #1? Were you able to determine that without solving? How?
  • How can you tell just by looking at Jessica’s quotient in #3 that she is incorrect? Why is her answer unreasonable?
  • What was the quotient in each part of #4? How did the given fact help you solve the rest?
  • Why are both Gil and Miriam’s methods in #5 correct? Which one do you gravitate toward with similar problems? Why?
  • How did you decide on what values to fill in the blanks in #8 to make the expression have the largest possible value? How did you decide on what values to fill in the blanks in the challenge in #3 to make the expression have a value as close to 30 as possible?
  • Explain the general method that we can use to determine where to place the decimal point in decimal division problems.

Target Task

5-10 minutes


Problem 1

Which expressions are equal to 9.45 ÷ 3.5? Select the two correct answers. 

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

Student Response

Upgrade to Fishtank Plus to view Sample Response.

Problem 2

Use the fact that $$288 \div 36 = 8$$ to find the quotient of 28.8 and 0.36. Explain how you decided where to place the decimal point.

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

Solve real-world problems that require interpretation of the remainder involving all possible cases, including further decomposition into a decimal.

Lesson 17
icon/arrow/right/large

Lesson Map

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

Topic A: Multiplying Decimals

Topic B: Dividing Decimals

Topic C: Decimal Expressions and Real-World Problems

Topic D: Measurement Conversion and Real-World 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