Multiplication and Division of Decimals

Lesson 20

Math

Unit 6

5th Grade

Lesson 20 of 24

Objective


Express measurements in a whole number of larger units or mixed units in terms of a smaller unit.

Common Core Standards


Core Standards

  • 5.MD.A.1 — Convert among different-sized standard measurement units within a given measurement system (e.g., convert 5 cm to 0.05 m), and use these conversions in solving multi-step, real world problems.

Foundational Standards

  • 4.MD.A.1

Criteria for Success


  1. Understand the meaning of different prefixes for metric units and how they relate to the base unit (e.g., kilo- means 1,000, so a kilogram is 1,000 times as large as a gram).
  2. Understand that a conversion factor is the factor in a multiplication sentence that renames one measurement unit as another equivalent unit.
  3. Convert from larger metric whole-number units to smaller ones, including mixed units (e.g., 6 kg 5g is how many grams?).
  4. Convert from larger customary whole-number units to smaller ones, including mixed units (e.g., 6 lb. 7 oz. is how many ounces?).
  5. Convert from larger whole-number units of time to smaller ones, including mixed units (e.g., 3 hr. 4 min. is how many seconds?).

Tips for Teachers


  • Lessons 20–24 have been designed with the Massachusetts Reference Sheet in mind. You should find the reference sheet that will be used on your state assessment so that you know the conversions students will need to memorize and those they will be given. Then revise Lessons 20–24 accordingly.
  • Lesson 20 encompasses learning students did in Grade 4 and is therefore optional. It is included in the unit, though, because later work is dependent on students’ understanding of the conversion factors and their ability to convert in simple cases. Because students do not receive a reference sheet in Grade 4 for state testing in Massachusetts, this lesson will also help students understand how to use this new resource for Grade 5.
  • “Students are not expected to know e.g. that there are 5280 feet in a mile. …It is worth having them realize that they need that information rather than giving it to them upfront; having students identify what information they need to have to solve the problem and knowing where to go to find it allows them to engage in Standard for Mathematical Practice 5, Use appropriate tools strategically” (MP.5) (Converting Fractions of a Unit into a Smaller Unit, Illustrative Math). Thus, provide students with a reference sheet only after they are able to identify the information they need but do not have, namely, the conversion factors.

Lesson Materials

Fishtank Plus

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

Anchor Tasks


Problem 1

Look at the following table regarding metric measurement prefixes:

SI Prefixes
Prefix Decimal English Word
Name Symbol
kilo k 1 000 thousand
    1 one
centi c 0.01 hundredth
milli m 0.001 thousandth

What do you notice? What do you wonder?

Guiding Questions

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

Problem 2

Fill in the blanks to make the following statements true.

a.   6 L = ________ mL

b.   34 kg = _________ g

c.   408 km = _________ cm

d.   53 cm 8 mm = ___________ mm

Guiding Questions

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

Problem 3

Fill in the blanks to make the following statements true.

a.   3 lb = ________ oz

b.   12 gal = _________ pt

c.   6 yd = _________ in

d.   3 qt 7 fl oz = ___________ fl oz

Guiding Questions

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

Problem 4

Fill in the blanks to make the following statements true.

a.   4 yr = ________ days

b.   1 wk = _________ min

c.   2 hr 8 min = ___________ sec

Guiding Questions

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

Problem Set


Answer Keys

Unlock the answer keys for this lesson's problem set and extra practice problems to save time and support student learning.

Discussion of Problem Set

  • How could #1(b) have helped you solve #1(h)?
  • How are #3(d) and #3(e) similar? How are they different?

Target Task


Problem 1

Convert pounds to ounces.

3 pounds = _________ ounces

Problem 2

Convert kilograms to grams.

18 kilograms = _________ grams

Student Response

Create a free account or sign in to view Student 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.

Extra Practice Problems

Answer Keys

Answer keys for Problem Sets and Extra Practice Problems are available with a Fishtank Plus subscription.

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.

icon/arrow/right/large copy

Lesson 19

icon/arrow/right/large

Lesson 21

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?

Effective Instruction Made Easy

Effective Instruction Made Easy

Access rigorous, relevant, and adaptable math lesson plans for free