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Virginia SOL Mathematics Textbook

Grade 6 Workbook — Chapter 5: Multiplying and Dividing Fractions

SOL 6.CE.1 a–c · Companion to Textbook Chapter 5

Each page below is one Canva page. Headings are sized for direct paste: page title as H1, section labels as H2. Figures referenced by filename live in ../figures/.


PAGE 1 — Chapter opener

Chapter 5 · Multiplying and Dividing Fractions

Standard 6.CE.1 a, b, c

In this chapter you will:

Words to know: factor · product · area model · set model · fraction strip · simplest form · dividend · divisor · quotient · improper fraction · reciprocal

Calculator note: parts a, b, and c of 6.CE.1 are assessed without a calculator. Do all of this chapter by hand.

Number limits for this chapter: denominators of 12 or less · proper fractions, improper fractions, and mixed numbers · every answer in simplest form


PAGE 2 — The area model

5.1 Modeling Fraction Multiplication

FIGURE: fig1-area-model-half-third.png (left half) [square in six cells, one column and one row hatched, overlap cell solid, showing 1/2 x 1/3 = 1/6]

"Of" means multiply. The double-shaded part of the square is the product.

Fill in the blanks.

In an area model, the number of equal cells equals the ____________ times the ____________.

The number of double-shaded cells equals the ____________ times the ____________.

Shade and solve. For each, write how many cells the square has, how many are double-shaded, and the product in simplest form.

Problem Total cells Double-shaded Product
12×14\tfrac{1}{2} \times \tfrac{1}{4}
25×13\tfrac{2}{5} \times \tfrac{1}{3}
34×12\tfrac{3}{4} \times \tfrac{1}{2}
23×25\tfrac{2}{3} \times \tfrac{2}{5}
23×34\tfrac{2}{3} \times \tfrac{3}{4}

PAGE 3 — Set models and strips

Groups and Strips

FIGURE: fig3-set-model-three-fourths-of-eight.png (full width) [eight circles in four groups of two, six filled, showing 3/4 of 8 = 6]

Fraction of a set.

34\tfrac{3}{4} of 88: each group has ______, take ______ groups, answer ______

13\tfrac{1}{3} of 99: each group has ______, take ______ groups, answer ______

23\tfrac{2}{3} of 1212: each group has ______, take ______ groups, answer ______

34\tfrac{3}{4} of 1616: each group has ______, take ______ groups, answer ______

FIGURE: fig4-strip-repeated-addition.png (full width) [three segments of 2/5 laid end to end on a number line from 0 to 2, total 6/5]

Repeated addition. Write each as a sum, then as a mixed number in simplest form.

3×25=3 \times \tfrac{2}{5} = ______________________ == ______

2×38=2 \times \tfrac{3}{8} = ______________________ == ______

5×23=5 \times \tfrac{2}{3} = ______________________ == ______

4×310=4 \times \tfrac{3}{10} = ______________________ == ______


PAGE 4 — Exit ticket 5.1

Exit Ticket · Lesson 5.1

Name: ________________________ Date: ____________

  1. 12×25=\tfrac{1}{2} \times \tfrac{2}{5} = ______ (simplest form)

  2. 34\tfrac{3}{4} of 16=16 = ______

  3. 4×310=4 \times \tfrac{3}{10} = ______ (mixed number, simplest form)

  4. Explain how an area model shows that 13×14=112\tfrac{1}{3} \times \tfrac{1}{4} = \tfrac{1}{12}.



PAGE 5 — The multiplication rule

5.2 Multiplying Fractions and Mixed Numbers

Multiply the numerators. Multiply the denominators. Simplify.

ab×cd=a×cb×d\frac{a}{b} \times \frac{c}{d} = \frac{a \times c}{b \times d}

Multiply. Show the unsimplified product, then the simplest form.

Problem Product before simplifying Simplest form
23×35\tfrac{2}{3} \times \tfrac{3}{5}
78×47\tfrac{7}{8} \times \tfrac{4}{7}
512×310\tfrac{5}{12} \times \tfrac{3}{10}
910×56\tfrac{9}{10} \times \tfrac{5}{6}
29×34\tfrac{2}{9} \times \tfrac{3}{4}
56×56\tfrac{5}{6} \times \tfrac{5}{6}

Convert to improper fractions.

112=02214=04258=008312=021\tfrac{1}{2} = \frac{\phantom{0}}{2} \qquad 2\tfrac{1}{4} = \frac{\phantom{0}}{4} \qquad 2\tfrac{5}{8} = \frac{\phantom{00}}{8} \qquad 3\tfrac{1}{2} = \frac{\phantom{0}}{2}


PAGE 6 — Mixed numbers and estimation

Multiplying Mixed Numbers

Estimate first, then compute. Write answers in simplest form.

Problem Estimate (round to whole numbers) Exact answer
112×231\tfrac{1}{2} \times \tfrac{2}{3}
225×1142\tfrac{2}{5} \times 1\tfrac{1}{4}
113×2141\tfrac{1}{3} \times 2\tfrac{1}{4}
312×1173\tfrac{1}{2} \times 1\tfrac{1}{7}
212×3152\tfrac{1}{2} \times 3\tfrac{1}{5}
4×2584 \times 2\tfrac{5}{8}
3×563 \times \tfrac{5}{6}

Apply it. A trail is 2232\tfrac{2}{3} miles long. Jonah walks 34\tfrac{3}{4} of it.

Estimate: ______ Exact distance: ______ miles

Predict. Will 78×45\tfrac{7}{8} \times \tfrac{4}{5} be greater or less than 45\tfrac{4}{5}? ______ Compute: ______


PAGE 7 — Exit ticket 5.2

Exit Ticket · Lesson 5.2

Name: ________________________ Date: ____________

Simplest form for every answer.

  1. 49×38=\tfrac{4}{9} \times \tfrac{3}{8} = ______

  2. 112×223=1\tfrac{1}{2} \times 2\tfrac{2}{3} = ______

  3. 6×512=6 \times \tfrac{5}{12} = ______

  4. Why do you convert a mixed number to an improper fraction before multiplying?



PAGE 8 — How many fit?

5.3 Modeling Fraction Division

FIGURE: fig5-strip-division-three-by-fourth.png (full width) [three whole strips each cut into fourths, twelve parts numbered, showing 3 divided by 1/4 = 12]

Read division as "how many of the divisor fit into the dividend?"

Count the pieces.

How many 14\tfrac{1}{4} fit into 3? ______ so 3÷14=3 \div \tfrac{1}{4} = ______

How many 13\tfrac{1}{3} fit into 2? ______ so 2÷13=2 \div \tfrac{1}{3} = ______

How many 18\tfrac{1}{8} fit into 1? ______ so 1÷18=1 \div \tfrac{1}{8} = ______

How many 12\tfrac{1}{2} fit into 4? ______ so 4÷12=4 \div \tfrac{1}{2} = ______

How many 13\tfrac{1}{3} fit into 5? ______ so 5÷13=5 \div \tfrac{1}{3} = ______

Common denominator strategy. Rename, then divide the numerators.

12÷18=08÷18=000\tfrac{1}{2} \div \tfrac{1}{8} = \tfrac{\phantom{0}}{8} \div \tfrac{1}{8} = \underline{\phantom{000}}

23÷16=06÷16=000\tfrac{2}{3} \div \tfrac{1}{6} = \tfrac{\phantom{0}}{6} \div \tfrac{1}{6} = \underline{\phantom{000}}

34÷18=08÷18=000\tfrac{3}{4} \div \tfrac{1}{8} = \tfrac{\phantom{0}}{8} \div \tfrac{1}{8} = \underline{\phantom{000}}


PAGE 9 — When part of one more fits

Quotients That Are Not Whole Numbers

FIGURE: fig6-strip-five-sixths-by-third.png (full width) [strip showing 5/6 shaded with thirds marked beneath, two whole thirds plus half of a third]

Complete.

In 56÷13\tfrac{5}{6} \div \tfrac{1}{3}, ______ whole thirds fit, using up 06\tfrac{\phantom{0}}{6}.

The leftover is 06\tfrac{\phantom{0}}{6}, which is ______ of a third.

So 56÷13=\tfrac{5}{6} \div \tfrac{1}{3} = ______

Divide.

a) 78÷18\tfrac{7}{8} \div \tfrac{1}{8} b) 56÷16\tfrac{5}{6} \div \tfrac{1}{6} c) 34÷14\tfrac{3}{4} \div \tfrac{1}{4}
d) 34÷12\tfrac{3}{4} \div \tfrac{1}{2} e) 3÷233 \div \tfrac{2}{3} f) 112÷141\tfrac{1}{2} \div \tfrac{1}{4}

Apply it. Nadia has 4124\tfrac{1}{2} feet of ribbon and cuts 34\tfrac{3}{4}-foot pieces. Number of pieces: ______

Explain. Why is 3÷143 \div \tfrac{1}{4} larger than 3?



PAGE 10 — Exit ticket 5.3

Exit Ticket · Lesson 5.3

Name: ________________________ Date: ____________

  1. 2÷15=2 \div \tfrac{1}{5} = ______

  2. 34÷18=\tfrac{3}{4} \div \tfrac{1}{8} = ______

  3. 56÷13=\tfrac{5}{6} \div \tfrac{1}{3} = ______

  4. How many 13\tfrac{1}{3}-cup scoops fill 2 cups? ______ What does that have to do with division?



PAGE 11 — Reciprocals

5.4 Dividing Fractions and Mixed Numbers

Two numbers are reciprocals when their product is 1. To divide by a fraction, multiply by its reciprocal.

Complete the reciprocal table.

Number 34\tfrac{3}{4} 15\tfrac{1}{5} 77 1121\tfrac{1}{2} 37\tfrac{3}{7} 55 29\tfrac{2}{9}
Reciprocal

Check one. 34×43=0012=\tfrac{3}{4} \times \tfrac{4}{3} = \tfrac{\phantom{00}}{12} = ______

Which number has no reciprocal? ______ Why?


Divide. Rewrite as multiplication first.

34÷25=34×00=0000\tfrac{3}{4} \div \tfrac{2}{5} = \tfrac{3}{4} \times \frac{\phantom{0}}{\phantom{0}} = \underline{\phantom{0000}}

58÷56=58×00=0000\tfrac{5}{8} \div \tfrac{5}{6} = \tfrac{5}{8} \times \frac{\phantom{0}}{\phantom{0}} = \underline{\phantom{0000}}

12÷34=12×00=0000\tfrac{1}{2} \div \tfrac{3}{4} = \tfrac{1}{2} \times \frac{\phantom{0}}{\phantom{0}} = \underline{\phantom{0000}}

23÷4=23×00=0000\tfrac{2}{3} \div 4 = \tfrac{2}{3} \times \frac{\phantom{0}}{\phantom{0}} = \underline{\phantom{0000}}


PAGE 12 — Division practice

Divide and Check

Divide. Simplest form.

a) 35÷25\tfrac{3}{5} \div \tfrac{2}{5} b) 56÷23\tfrac{5}{6} \div \tfrac{2}{3} c) 710÷78\tfrac{7}{10} \div \tfrac{7}{8}
d) 910÷35\tfrac{9}{10} \div \tfrac{3}{5} e) 512÷56\tfrac{5}{12} \div \tfrac{5}{6} f) 6÷386 \div \tfrac{3}{8}
g) 214÷122\tfrac{1}{4} \div \tfrac{1}{2} h) 313÷2123\tfrac{1}{3} \div 2\tfrac{1}{2} i) 412÷1184\tfrac{1}{2} \div 1\tfrac{1}{8}
j) 113÷231\tfrac{1}{3} \div \tfrac{2}{3} k) 3÷1123 \div 1\tfrac{1}{2} l) 712÷7\tfrac{7}{12} \div 7

Check by multiplying. Multiply your answer to (a) by 25\tfrac{2}{5}. Do you get 35\tfrac{3}{5} back? ______

Show the work: _______________________________________________

Apply it. A recipe uses 1141\tfrac{1}{4} cups of flour per batch. Priya has 7127\tfrac{1}{2} cups.

Full batches: ______


PAGE 13 — Exit ticket 5.4

Exit Ticket · Lesson 5.4

Name: ________________________ Date: ____________

Simplest form for every answer.

  1. 45÷23=\tfrac{4}{5} \div \tfrac{2}{3} = ______

  2. 312÷78=3\tfrac{1}{2} \div \tfrac{7}{8} = ______

  3. 58÷5=\tfrac{5}{8} \div 5 = ______

  4. Reciprocal of 37\tfrac{3}{7}: ______ of 55: ______ of 1121\tfrac{1}{2}: ______


PAGE 14 — Bigger or smaller?

5.5 Multiplying and Dividing by a Number Between 0 and 1

FIGURE: fig7-number-line-scaling.png (full width) [number line 0 to 20 with arrows from 12 to 9 for times 3/4, from 12 to 16 for divided by 3/4, and a loop at 12 for times 1]

Complete the rule table.

Operation on a positive number nn Result is…
multiply by a number between 0 and 1
multiply by exactly 1
multiply by a number greater than 1
divide by a number between 0 and 1
divide by a number greater than 1

Predict, then compute.

Problem More or less than the start? Answer
20×2520 \times \tfrac{2}{5}
20÷2520 \div \tfrac{2}{5}
10×3510 \times \tfrac{3}{5}
10÷3510 \div \tfrac{3}{5}
34×45\tfrac{3}{4} \times \tfrac{4}{5}
6÷126 \div \tfrac{1}{2}

PAGE 15 — Sorting and disproving

Sort and Explain

Sort each expression by its result compared to 9.

9×139×329×569×19÷349÷39 \times \tfrac{1}{3} \qquad 9 \times \tfrac{3}{2} \qquad 9 \times \tfrac{5}{6} \qquad 9 \times 1 \qquad 9 \div \tfrac{3}{4} \qquad 9 \div 3

Less than 9 Equal to 9 Greater than 9

Compute and compare.

212×45=2\tfrac{1}{2} \times \tfrac{4}{5} = ______ which is ____________ than 2122\tfrac{1}{2}

212÷45=2\tfrac{1}{2} \div \tfrac{4}{5} = ______ which is ____________ than 2122\tfrac{1}{2}

Apply it. A photo is 8 inches wide.

Scaled by 34\tfrac{3}{4}: ______ inches. Scaled by 54\tfrac{5}{4}: ______ inches.

Which factor enlarges the photo? ______ Why?


Disprove it. Jaden says multiplying always makes a number bigger and dividing always makes it smaller. Give one counterexample of each kind.

Multiplication: _______________ Division: _______________

What condition did he leave out? _______________________________________________


PAGE 16 — Exit ticket 5.5

Exit Ticket · Lesson 5.5

Name: ________________________ Date: ____________

  1. Is 16×5816 \times \tfrac{5}{8} more or less than 16? ______ Answer: ______

  2. Is 16÷5816 \div \tfrac{5}{8} more or less than 16? ______ Answer: ______

  3. 34×23=\tfrac{3}{4} \times \tfrac{2}{3} = ______ which is ____________ than 34\tfrac{3}{4}

  4. Why does multiplying by 58\tfrac{5}{8} shrink a number while multiplying by 85\tfrac{8}{5} grows it?



PAGE 17 — Chapter 5 review, part 1

Chapter 5 Review

Part A · Modeling

  1. Area model for 23×12\tfrac{2}{3} \times \tfrac{1}{2}. Product: ______

  2. Strip model for 34÷18\tfrac{3}{4} \div \tfrac{1}{8}. Quotient: ______

  3. Repeated addition: 4×23=4 \times \tfrac{2}{3} = ______ (mixed number)

  4. Set model: 35\tfrac{3}{5} of 10=10 = ______

Part B · Multiplying and dividing

Simplest form for every answer.

  1. a) 38×23\tfrac{3}{8} \times \tfrac{2}{3} ______ b) 59×310\tfrac{5}{9} \times \tfrac{3}{10} ______ c) 712×67\tfrac{7}{12} \times \tfrac{6}{7} ______

  2. a) 112×2251\tfrac{1}{2} \times 2\tfrac{2}{5} ______ b) 213×1122\tfrac{1}{3} \times 1\tfrac{1}{2} ______

  3. a) 34÷38\tfrac{3}{4} \div \tfrac{3}{8} ______ b) 56÷512\tfrac{5}{6} \div \tfrac{5}{12} ______ c) 25÷4\tfrac{2}{5} \div 4 ______

  4. a) 412÷344\tfrac{1}{2} \div \tfrac{3}{4} ______ b) 313÷1233\tfrac{1}{3} \div 1\tfrac{2}{3} ______

  5. 8÷23=8 \div \tfrac{2}{3} = ______


PAGE 18 — Chapter 5 review, part 2

Chapter 5 Review (continued)

Part C · Multiplying and dividing by a number between 0 and 1

  1. More or less than 24, then compute: a) 24×5624 \times \tfrac{5}{6} ______ , ______ b) 24÷5624 \div \tfrac{5}{6} ______ , ______

  2. Why is 12×12\tfrac{1}{2} \times \tfrac{1}{2} less than 12\tfrac{1}{2}?


  3. Which results are greater than 78\tfrac{7}{8}? Compute each.

    78×43=\tfrac{7}{8} \times \tfrac{4}{3} = ______ 78÷43=\tfrac{7}{8} \div \tfrac{4}{3} = ______ 78×23=\tfrac{7}{8} \times \tfrac{2}{3} = ______

    Greater than 78\tfrac{7}{8}: _______________

Part D · Application and reasoning

  1. Each bag holds 34\tfrac{3}{4} pound. 2122\tfrac{1}{2} bags hold ______ pounds.

  2. A board 5145\tfrac{1}{4} ft long is cut into 34\tfrac{3}{4}-ft pieces. Number of pieces: ______

  3. 56÷16=5\tfrac{5}{6} \div \tfrac{1}{6} = 5 but 56×16=536\tfrac{5}{6} \times \tfrac{1}{6} = \tfrac{5}{36}. Why so different?


  4. Check 34÷25\tfrac{3}{4} \div \tfrac{2}{5} using multiplication. Show the check and explain why it works.



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