# Unit Conversions

## Objective

Solve word problems involving converting fractional and decimal measurements to a smaller unit.

## Common Core Standards

### Core Standards

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• 4.MD.A.2 — Use the four operations to solve word problems involving distances, intervals of time, liquid volumes, masses of objects, and money, including problems involving simple fractions or decimals, and problems that require expressing measurements given in a larger unit in terms of a smaller unit. Represent measurement quantities using diagrams such as number line diagrams that feature a measurement scale.

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• 3.MD.A.1

• 3.MD.A.2

• 4.OA.A.3

## Criteria for Success

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1. Solve word problems involving converting decimal measurements to a smaller unit (MP.4).
2. Solve word problems involving converting fractional measurements to a smaller unit (MP.4).

## Tips for Teachers

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Let students work on each problem in the Problem Set independently and circulate to see whether students are solving correctly. If not, come back together to discuss how/what to draw on a tape diagram, then allow them to try again on their own.

#### Fishtank Plus

• Problem Set
• Student Handout Editor
• Vocabulary Package

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### Problem 1

Watch the following video: The Water Boy (Act-1).

 Here is how much water the water bottle holds: Here is how much water is left in the bottle:

How much water is left in the bottle?

#### References

Questioning My Metacognition The Water Boy

The Water Boy by Graham Fletcher is made available on Questioning My Metacognition under the CC BY-SA 4.0 license. Accessed June 13, 2018, 4:58 p.m..

Modified by The Match Foundation, Inc.

### Problem 2

Watch the following video: Act 1: On a Roll.

• This is how much tape she has:

• The length of the dry erase board is $1\frac{5}{12}$ feet and the width of the dry erase board is $1\frac{11}{12}$ feet.

Will she have enough tape to cover the border of the dry erase board?

#### References

Ms Castillos Math 3 Act: On a Roll

3 Act: On a Roll by Catherine Castillo is made available on Ms Castillos Math. Accessed June 29, 2018, 11:02 a.m..

Modified by The Match Foundation, Inc.

## Discussion of Problem Set

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• How did you interpret the remainder in #2?
• In #7(a), how many different ways were 7 halves represented? (30 min 7, as ${{7\over2}}$ and as ${{6\over2}+{1\over2}}$) What advantage is there to knowing all of these representations when it comes to solving a problem like this one?
• What shortcuts or efficiencies did you use today when solving your problems? How do you decide whether to start by converting to a smaller unit or to work with the mixed number or decimal measurements?

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### Problem 1

Solve. Show or explain your work.

It took Gigi ${1{1\over3}}$ hour and to complete a bicycle race. It took Johnny twice as long because he got a flat tire. How many minutes did it take Johnny to finish the race?

#### References

EngageNY Mathematics Grade 4 Mathematics > Module 7 > Topic C > Lesson 14Exit Ticket, Question #1

Grade 4 Mathematics > Module 7 > Topic C > Lesson 14 of the New York State Common Core Mathematics Curriculum from EngageNY and Great Minds. © 2015 Great Minds. Licensed by EngageNY of the New York State Education Department under the CC BY-NC-SA 3.0 US license. Accessed Dec. 2, 2016, 5:15 p.m..

Modified by The Match Foundation, Inc.

### Problem 2

Mary and her friends are making fruit punch. They combine 1.5 liters of lemonade, 3 liters of pineapple juice, and 0.25 liters of cranberry juice. How many total milliliters of fruit punch did they make?

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