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Virginia SOL Mathematics Textbook

Grade 7 Workbook — Chapter 4: Operations with Rational Numbers in Context

SOL 7.CE.1 · Companion to Textbook Chapter 4

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/. Every numbered item is the same problem as in the textbook, so one answer key serves both.


PAGE 1 — Chapter opener

Chapter 4 · Operations with Rational Numbers in Context

Standard 7.CE.1

In this chapter you will:

Words to know: rational number · proper fraction · improper fraction · mixed number · thousandths place · common denominator · reciprocal · estimate · bracket · compatible numbers · multistep problem · justify

Calculator note: a calculator is allowed in this chapter. It will faithfully compute a mistyped number, so every page asks you to estimate first.


PAGE 2 — Signed changes on a number line

4.1 Adding and Subtracting Rational Numbers

FIGURE: fig1-temperature-drop.png (full width)

Fill in the blanks.

Adding a positive number moves you to the ________ on a number line.

Adding a negative number moves you to the ________.

To subtract, add the ______________: ab=a+(a - b = a + ( ______ )).

Decimals in this chapter go no further than the ______________ place.

Write each situation as a signed number.

Situation Signed number
A deposit of $45.50
A temperature fall of 12.2512.25 degrees
Descending 6.256.25 ft underwater
A withdrawal of $18.60
Rising 9.759.75 ft toward the surface

PAGE 3 — Fractions need common denominators

Common Denominators in Context

FIGURE: fig5-fraction-difference.png (full width)

314=    8158=    8difference=    8=3\tfrac{1}{4} = \frac{\ \ \ \ }{8} \qquad 1\tfrac{5}{8} = \frac{\ \ \ \ }{8} \qquad \text{difference} = \frac{\ \ \ \ }{8} = \underline{\qquad}

Guided practice

  1. Find 7.4+12.9-7.4 + 12.9. Sign of the answer: ________ Size: ________ Answer: ________

  2. Find 214+(534)2\tfrac{1}{4} + \left(-5\tfrac{3}{4}\right). ________

  3. Rewrite 6.2(3.85)6.2 - (-3.85) as addition: _______________ Answer: ________

  4. At 5 p.m. the temperature is 2.5-2.5°C. It drops 4.754.75°C overnight. Morning temperature: ________

  5. Devon's balance is $34.20. He writes a check for $52.75. New balance: ________

    What does the sign of your answer mean?



PAGE 4 — Independent practice 4.1

Practice · Adding and Subtracting

FIGURE: fig2-elevation-dive.png (right third of page)

  1. Evaluate.
a) 9.6+4.25-9.6 + 4.25 b) 323+114-3\tfrac{2}{3} + 1\tfrac{1}{4}
c) 7.511.3757.5 - 11.375 d) 56(13)-\tfrac{5}{6} - \left(-\tfrac{1}{3}\right)
  1. A hiker starts at 1,240.51{,}240.5 ft, descends 386.75386.75 ft, then climbs 152.25152.25 ft. Final elevation: ________

  2. An account is at $42.15-\$42.15. A $120.00 deposit arrives; charges of $18.60 and $35.75 post. Final balance: ________

  3. A jug holds 7127\tfrac{1}{2} qt of cider. Two pitchers take 2342\tfrac{3}{4} qt and 1581\tfrac{5}{8} qt. Remaining: ________

  4. Daily price changes: 1.25-1.25, +0.875+0.875, 2.5-2.5, +3.125+3.125. Total change: ________ Higher or lower? ________

  5. Application. At 6 a.m. it is 6.5-6.5°F. It rises 13.2513.25 degrees by noon, then falls 8.758.75 degrees by 9 p.m.

    Noon: ________ 9 p.m.: ________

  6. Reasoning. Jordan writes 4.62.8=1.8-4.6 - 2.8 = -1.8. Correct answer: ________

    What did Jordan misread?



PAGE 5 — Exit ticket 4.1

Exit Ticket · Lesson 4.1

Name: ________________________ Date: ____________

  1. Find 8.25+3.5-8.25 + 3.5. ________

  2. Find 1564131\tfrac{5}{6} - 4\tfrac{1}{3}. ________

  3. A balance of $16.40-\$16.40 receives a $25.00 deposit. New balance: ________

  4. Using a situation of your choice, explain why subtracting a negative number makes a result larger.




PAGE 6 — Sign rules

4.2 Multiplying and Dividing Rational Numbers

Complete the sign table.

Factors Sign of product or quotient
positive ×\times positive
positive ×\times negative
negative ×\times positive
negative ×\times negative

Continue the pattern to see why two negatives give a positive.

(4.5)(2)=(4.5)(1)=(4.5)(0)=(4.5)(1)=(-4.5)(2) = \underline{\qquad} \quad (-4.5)(1) = \underline{\qquad} \quad (-4.5)(0) = \underline{\qquad} \quad (-4.5)(-1) = \underline{\qquad}

Each time the second factor drops by 1, the product goes ________ by 4.54.5.

Two kinds of division. Label each problem sharing or measuring.

Problem Sharing or measuring?
A $73.50 charge split among 5 people
A 121212\tfrac{1}{2}-ft ribbon cut into 58\tfrac{5}{8}-ft pieces
6386\tfrac{3}{8} cups poured into 34\tfrac{3}{4}-cup bowls
$146.20 divided among 4 friends

PAGE 7 — Guided practice 4.2

Guided Practice · Multiplying and Dividing

To divide by a fraction, multiply by its reciprocal.

518÷34=518×        =        =\frac{51}{8} \div \frac{3}{4} = \frac{51}{8} \times \frac{\ \ \ \ }{\ \ \ \ } = \frac{\ \ \ \ }{\ \ \ \ } = \underline{\qquad}

  1. (7)(2.5)(-7)(2.5) Sign: ________ Answer: ________

  2. (35)(109)\left(-\tfrac{3}{5}\right)\left(-\tfrac{10}{9}\right) in simplest form: ________

  3. 20.4÷6=-20.4 \div 6 = ________

  4. 514÷(112)5\tfrac{1}{4} \div \left(-1\tfrac{1}{2}\right)

    As improper fractions: ______ ÷\div ______ Answer: ________

  5. A well drops 0.3750.375 ft each day. Change after 8 days: ________


PAGE 8 — Independent practice 4.2

Practice · Multiplying and Dividing

  1. Evaluate.
a) (1.2)(4.5)(-1.2)(-4.5) b) (78)(23)\left(-\tfrac{7}{8}\right)\left(\tfrac{2}{3}\right)
c) 15.75÷(2.5)-15.75 \div (-2.5) d) (223)÷45\left(-2\tfrac{2}{3}\right) \div \tfrac{4}{5}
  1. Four friends split a $146.20 bill equally. Each pays: ________

  2. A recipe uses 2132\tfrac{1}{3} cups of flour per batch. Flour for 2142\tfrac{1}{4} batches: ________

  3. A scuba tank loses 8.758.75 psi each minute. Change after 7.27.2 minutes: ________

  4. A submarine descends 12.512.5 ft per minute for 6.46.4 minutes. Change in elevation: ________

  5. Application. 101210\tfrac{1}{2} cups of chili served in 1121\tfrac{1}{2}-cup portions. Portions: ________

    How do you know none is left over?


  6. Reasoning. Why is the quotient of two negatives positive? Use a real situation, not just the rule.




PAGE 9 — Exit ticket 4.2

Exit Ticket · Lesson 4.2

Name: ________________________ Date: ____________

  1. (6)(3.5)=(-6)(-3.5) = ________

  2. (34)(89)=\left(-\tfrac{3}{4}\right)\left(\tfrac{8}{9}\right) = ________

  3. 22.5÷4.5=-22.5 \div 4.5 = ________

  4. A quotient contains exactly one negative number. What is its sign, and how do you know?



PAGE 10 — Three ways to estimate

4.3 Estimating to Judge Reasonableness

FIGURE: fig3-estimation-bracket.png (full width)

Complete the three strategies for 6.85×2.406.85 \times 2.40.

Strategy Work Estimate
Rounding 7×2.407 \times 2.40
Low estimate (round both down) 6.5×26.5 \times 2
High estimate (round both up) 7×2.57 \times 2.5

Exact product: ________ Does it land inside the bracket? ________

Two errors a calculator cannot catch:

  1. a misplaced ______________ ______________

  2. a dropped ______________ ______________

Warning. Dividing by a number less than 1 makes the result ______________.


PAGE 11 — Guided practice 4.3

Guided Practice · Estimating

  1. 8.9×3.18.9 \times 3.1 Estimate: ________ Exact: ________

  2. 19.6÷4.9-19.6 \div 4.9 Compatible numbers: ______ ÷\div ______ Estimate: ______ Exact: ______

  3. 518+2785\tfrac{1}{8} + 2\tfrac{7}{8} Estimate: ________ Exact: ________

  4. A student reports 6.4×0.52=33.286.4 \times 0.52 = 33.28.

    Estimate: ________ Reasonable? ________ Correct answer: ________

  5. 3.7×4.63.7 \times 4.6 Low estimate: ______ High estimate: ______ Exact: ______

    Inside the bracket? ________


PAGE 12 — Independent practice 4.3

Practice · Estimating and Judging

  1. Estimate, then find the exact value.
Estimate Exact
a) 12.3×4.812.3 \times 4.8
b) 44.8÷5.6-44.8 \div 5.6
c) 934+4189\tfrac{3}{4} + 4\tfrac{1}{8}
d) 745×27\tfrac{4}{5} \times 2
  1. 8.3×6.78.3 \times 6.7 Low: ______ High: ______ Exact: ______

  2. Reasonable or not? Give a one-line estimate and correct any that are wrong.

Reported answer Estimate Reasonable? Correction
a) 4.9×5.1=24.994.9 \times 5.1 = 24.99
b) 63.9÷7.1=9063.9 \div 7.1 = 90
c) 3.2×6.5=20.8-3.2 \times 6.5 = 20.8
d) 19.6+(4.85)=14.7519.6 + (-4.85) = 14.75
  1. Application. Gas costs $3.199 per gallon. Estimate the cost of 11.411.4 gallons: ________

    Exact, rounded to the nearest cent: ________

  2. Application. Five friends split $97.35. Estimate: ________ Exact: ________

  3. Application. Four tickets at $13.75 plus $8.50 parking. Is $60 enough? ________ Exact total: ________

  4. Reasoning. Why does rounding both factors up always overshoot a product of two positives, and why is a low-and-high pair more useful than one estimate?



PAGE 13 — Exit ticket 4.3

Exit Ticket · Lesson 4.3

Name: ________________________ Date: ____________

  1. 7.8×4.27.8 \times 4.2 Estimate: ________ Exact: ________

  2. Is 56.4÷7.05=8-56.4 \div 7.05 = 8 reasonable? ________ Correct answer: ________

  3. 6.4×3.76.4 \times 3.7 Low: ______ High: ______ Exact: ______

  4. How can an estimate catch a misplaced decimal point that a calculator will not?



PAGE 14 — The four-move plan

4.4 Multistep Problems in Context

FIGURE: fig4-bar-model-split.png (full width)

The plan.

  1. Understand — what is asked, and in what ______________?
  2. Estimate — a rough answer with friendly numbers.
  3. Solve — steps in order, each labeled.
  4. Check — compare to the estimate and work ______________.

Order matters. For a $78.60 bill with a $12.60 coupon split 3 ways:

Subtract first: 78.6012.60=78.60 - 12.60 = ________ then divide: ÷ 3=\div\ 3 = ________

Why can't you divide first?


Rate over time.

final value=starting value+(rate×time)\text{final value} = \text{starting value} + (\text{rate} \times \text{time})

4.5+(1.75)(6)=4.5 + (-1.75)(6) = ________


PAGE 15 — Guided practice 4.4

Guided Practice · Multistep Problems

  1. A $44.80 bill less a $4.80 discount, split 4 ways.

    After discount: ________ Each pays: ________

  2. Temperature 3.5-3.5°C, rising 2.252.25°C per hour for 4 hours.

    Total change: ________ Final temperature: ________

  3. Cheese at $6.40 per pound. Cost of 2342\tfrac{3}{4} pounds: ________

  4. A 20-gallon tank losing 1.3751.375 gal per hour for 6 hours.

    Water lost: ________ Water remaining: ________

  5. A 121212\tfrac{1}{2}-ft ribbon cut into 58\tfrac{5}{8}-ft pieces. Number of pieces: ________


PAGE 16 — Independent practice 4.4

Practice · Multistep Problems

  1. $24.99 per month plus $0.045 per extra minute, with 60 extra minutes.

    Extra-minute charge: ________ Total bill: ________

  2. A hiker at 2,150.52{,}150.5 ft descends 128.25128.25 ft per hour for 6 hours.

    Total descent: ________ Final elevation: ________

  3. Three rooms at 1341\tfrac{3}{4} gal each; you have 4124\tfrac{1}{2} gal.

    Paint needed: ________ More paint required: ________

  4. Balance $28.35-\$28.35; a $150.00 deposit; four withdrawals of $22.50.

    Withdrawals total: ________ Final balance: ________

  5. Twenty shares bought at $18.75; the price falls $0.625 per day for 6 days.

    Total price drop: ________ New price per share: ________ Total loss on 20 shares: ________

  6. Application. 27 students; $8.75 admission each; $148.50 bus shared equally.

    Admission total: ________ Grand total: ________ Each student pays: ________

  7. Reasoning. For item 49, a student divided by 4 first and then subtracted $4.80 from each share.

    That student's answer: ________ Why is the order wrong?



PAGE 17 — Exit ticket 4.4

Exit Ticket · Lesson 4.4

Name: ________________________ Date: ____________

  1. A $56.40 bill less a $6.40 gift card, split 5 ways. Each pays: ________

  2. Temperature 2.52.5°F falling 1.251.25°F per hour for 6 hours. Final: ________

  3. 8238\tfrac{2}{3} cups of soup in 23\tfrac{2}{3}-cup bowls. Bowls filled: ________

  4. Describe the check you would use to confirm item 62 is reasonable.



PAGE 18 — The three parts of a justification

4.5 Justifying a Solution

A complete justification has three parts.

  1. An ______________ showing roughly where the answer had to land, including its ______________.
  2. The ______________ you chose, and why each matches the situation.
  3. An answer ______________ with units, plus a ______________ when one is available.

Model it. Three friends split a $47.25 bill after a $5.25 coupon.

Part Your writing
Estimate
Operations and why
Computation
Answer sentence
Check (work backward)

Error analysis is justification in reverse. A student evaluates 12.6+4.2×3-12.6 + 4.2 \times 3 as 25.2-25.2.

What did the student do first? _______________________

Correct value: ________


PAGE 19 — Guided practice 4.5

Guided Practice · Justifying

  1. Write a one-sentence estimate justifying 9.8×5.2=50.969.8 \times 5.2 = 50.96.


  2. A 6146\tfrac{1}{4}-lb bag of rice repackaged into 58\tfrac{5}{8}-lb bags.

    Operation: ______________ Why: _______________________

    Number of bags: ________

  3. A student writes 5.6(2.4)=8.0-5.6 - (-2.4) = -8.0. Error: _______________________

    Correct answer: ________

  4. Temperature 1.51.5°F falling 2.52.5°F per hour for 3 hours.

    Why must the answer be negative? _______________________

    Answer: ________

  5. Five friends split $81.25 evenly.

    Estimate: ________ Operation and reason: _______________________

    Answer sentence: _______________________


PAGE 20 — Independent practice 4.5

Practice · Justifying and Error Analysis

  1. A student writes 23×(34)=112\tfrac{2}{3} \times \left(-\tfrac{3}{4}\right) = -\tfrac{1}{12}.

    Error: _______________________ Correct product: ________

  2. A student reports 18.6÷0.3=0.6218.6 \div 0.3 = 0.62.

    Estimate showing it is wrong: ________ Correct quotient: ________

  3. Seven friends split a $103.60 bill after a $5.25 coupon. Write a complete justification.

Part Your writing
Estimate
Operations and why
Computation
Answer sentence
Check
  1. Application. A pool loses 0.3750.375 in of water per day. Change after 12 days: ________

    Justify the sign and the size: _______________________

  2. Application. 1131\tfrac{1}{3} cups of sugar for 8 servings. Sugar for 20 servings: ________

    Scaling factor and why: _______________________

  3. Reasoning. Two students answer item 72 with $14.05 and $14.50. Which is right, and how does estimation tell you without redoing the division?


  4. Reasoning. Why is "I checked by working backward" stronger than "I used a calculator"?



PAGE 21 — Exit ticket 4.5

Exit Ticket · Lesson 4.5

Name: ________________________ Date: ____________

  1. Write an estimate justifying 6.1×3.9=23.79-6.1 \times 3.9 = -23.79, covering both size and sign.

  1. A student writes 312÷12=1343\tfrac{1}{2} \div \tfrac{1}{2} = 1\tfrac{3}{4}. Error: _______________ Correct: ________

  2. Justify why four people splitting $63.80 each pay $15.95. Include a check.


  1. Name the three parts of a complete justification.


PAGE 22 — Chapter 4 review, part 1

Chapter 4 Review

Part A · Adding and subtracting

  1. Evaluate.
a) 14.75+6.5-14.75 + 6.5 b) 238156-2\tfrac{3}{8} - 1\tfrac{5}{6}
c) 9.6(3.45)9.6 - (-3.45) d) 514+(712)5\tfrac{1}{4} + \left(-7\tfrac{1}{2}\right)
  1. Balance $52.80-\$52.80; $140.00 deposit; $36.45 withdrawal. Final balance: ________

  2. Temperature 1.51.5°F falls 9.259.25 degrees, then rises 3.753.75 degrees. Final: ________

Part B · Multiplying and dividing

  1. Evaluate.
a) (8)(2.75)(-8)(2.75) b) (35)(56)\left(-\tfrac{3}{5}\right)\left(-\tfrac{5}{6}\right)
c) 33.6÷(4.2)-33.6 \div (-4.2) d) 623÷(113)6\tfrac{2}{3} \div \left(-1\tfrac{1}{3}\right)
  1. A 9349\tfrac{3}{4}-ft rope cut into 34\tfrac{3}{4}-ft pieces. Pieces: ________

  2. A tank drains 2.1252.125 gal per minute for 8 minutes. Change in volume: ________


PAGE 23 — Chapter 4 review, part 2

Chapter 4 Review (continued)

Part C · Estimating

  1. Estimate, then find the exact value.
Estimate Exact
a) 11.8×5.111.8 \times 5.1
b) 71.4÷8.4-71.4 \div 8.4
c) 678+3186\tfrac{7}{8} + 3\tfrac{1}{8}
  1. 5.6×7.35.6 \times 7.3 Low: ______ High: ______ Exact: ______ Inside? ______

  2. Reasonable or not? Correct any that are wrong.

Reported answer Estimate Reasonable? Correction
a) 4.05×19.8=80.194.05 \times 19.8 = 80.19
b) 12.6÷0.3=4.212.6 \div 0.3 = 4.2
c) 7.5+2.25=9.75-7.5 + 2.25 = 9.75

Part D · Multistep problems

  1. $96.40 catering less a $14.40 coupon, split 4 ways. Each pays: ________

  2. 24 students; $6.25 admission; $114.00 bus shared. Each pays: ________

  3. 3123\tfrac{1}{2} cups of stock for 6 servings. Stock for 15 servings: ________

  4. A drone at 96.596.5 ft descends 14.2514.25 ft per second for 6 seconds, then rises 8.58.5 ft. Final height: ________


PAGE 24 — Chapter 4 review, part 3

Chapter 4 Review (continued)

Part E · Reasoning and justification

  1. A student evaluates 18.4+6.2×2-18.4 + 6.2 \times 2 as 24.4-24.4.

    Error: _______________________ Correct value: ________

  2. Six friends split a $77.70 bill evenly. Write a complete justification.

Part Your writing
Estimate
Operation and why
Computation
Answer sentence
Check
  1. Why is estimating first worth the time even when a calculator is allowed? Name one specific error an estimate catches and a calculator does not.




Canva production notes