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Fraction Operations

A comprehensive sequence covering fraction multiplication with cross-cancelling techniques and fraction division using reciprocals.

Ttsthibeault
Cross Cancelling Fractions

A collection of worksheets and practice materials focused on multiplying signed fractions and mixed numbers using cross-cancelling techniques.

Dividing Fractions

Instructional materials introducing fraction division through reciprocal multiplication and the Keep Change Flip strategy.

Fraction Operations

A comprehensive sequence covering fraction multiplication with cross-cancelling techniques and fraction division using reciprocals.

Ttsthibeault
  1. Ans: \(\frac{9}{4}\) or \(2\frac{1}{4}\)

\(\displaystyle {\left(-\frac{15}{8}\right) \times \left(-\frac{6}{5}\right)}\)

Cancel 15 & 5 (3, 1); 6 & 8 (3, 4)
\(= \frac{3 \times 3}{4 \times 1} = \mathbf{\frac{9}{4}}\text{ or }\mathbf{2\frac{1}{4}}\)

  1. Ans: \(-\frac{7}{2}\) or \(-3\frac{1}{2}\)

\(\displaystyle {\left(-\frac{10}{3}\right) \times \frac{21}{20}}\)

Cancel 10 & 20 (1, 2); 3 & 21 (1, 7)
\(= -\frac{1 \times 7}{1 \times 2} = \mathbf{-\frac{7}{2}}\text{ or }\mathbf{-3\frac{1}{2}}\)

Answers

  1. \(-\frac{1}{4}\)

  2. \(-\frac{1}{4}\)

  3. \(\frac{1}{6}\)

  4. \(\frac{1}{9}\)

  5. \(-\frac{1}{6}\)

  6. \(-\frac{1}{6}\)

  7. \(\frac{1}{12}\)

  8. \(-\frac{4}{35}\)

  9. \(-\frac{3}{4}\)

  10. \(-\frac{3}{2}\) / \(-1\frac{1}{2}\)

  11. \(\frac{9}{4}\) / \(2\frac{1}{4}\)

  12. \(-\frac{7}{2}\) / \(-3\frac{1}{2}\)

Pair 2: 10 & 25 GCF:

Factor pairs (10):

Factor pairs (25):

  1. \(-1\frac{1}{5} \rightarrow -\frac{6}{5} \times \frac{5}{8}\)

Pair 1: 6 & 8 GCF:

Factor pairs (6):

Factor pairs (8):

Pair 2: 5 & 5 GCF:

Factor pairs (5):

Factor pairs (5):

  1. \(2\frac{2}{3} \rightarrow \frac{8}{3} \times \left(-\frac{9}{16}\right)\)

Pair 1: 8 & 16 GCF:

Factor pairs (8):

Factor pairs (16):

Pair 2: 9 & 3 GCF:

Factor pairs (9):

Factor pairs (3):

  1. \(-\frac{15}{8} \times \left(-\frac{6}{5}\right)\)

Pair 1: 15 & 5 GCF:

Factor pairs (15):

Factor pairs (5):

Pair 2: 6 & 8 GCF:

Factor pairs (6):

Factor pairs (8):

  1. \(-\frac{10}{3} \times \frac{21}{20}\)

Pair 1: 10 & 20 GCF:

Factor pairs (10):

Factor pairs (20):

Pair 2: 21 & 3 GCF:

Factor pairs (21):

Factor pairs (3):

* For mixed numbers (9–12), convert to improper fractions first to reveal the diagonal numerator and denominator pairs. Factor Pairs Organizer

  • Ans: \(-\frac{25}{7}\)
  • \(\displaystyle {-\frac{5}{2} \times \frac{10}{7}}\)

    Cancel 2 & 10 by 2 (1, 5) \(\rightarrow \mathbf{-\frac{25}{7}\text{ or }-3\frac{4}{7}}\)

    1. Ans: \(-\frac{65}{6}\)

    \(\displaystyle {\frac{10}{3} \times \left(-\frac{13}{4}\right)}\)

    Cancel 10 & 4 by 2 (5, 2) \(\rightarrow \mathbf{-\frac{65}{6}\text{ or }-10\frac{5}{6}}\)

    1. Ans: \(\frac{85}{14}\)

    \(\displaystyle {-\frac{17}{8} \times \left(-\frac{20}{7}\right)}\)

    Cancel 8 & 20 by 4 (2, 5) \(\rightarrow \mathbf{\frac{85}{14}\text{ or }6\frac{1}{14}}\)

    1. Ans: \(-\frac{33}{14}\)

    \(\displaystyle {-\frac{11}{8} \times \frac{12}{7}}\)

    Cancel 8 & 12 by 4 (2, 3) \(\rightarrow \mathbf{-\frac{33}{14}\text{ or }-2\frac{5}{14}}\)

    1. Ans: \(-\frac{5}{4}\)

    \(\displaystyle {\frac{7}{8} \times \left(-\frac{10}{7}\right)}\)

    Cancel 7 & 7 (1, 1); 8 & 10 (4, 5) \(\rightarrow \mathbf{-\frac{5}{4}\text{ or }-1\frac{1}{4}}\)

    1. Ans: \(\frac{25}{18}\)

    \(\displaystyle {-\frac{10}{9} \times \left(-\frac{5}{4}\right)}\)

    Cancel 10 & 4 by 2 (5, 2) \(\rightarrow \mathbf{\frac{25}{18}\text{ or }1\frac{7}{18}}\)

    Answers

    1. \(-\frac{2}{15}\)

    2. \(-\frac{1}{3}\)

    3. \(\frac{1}{5}\)

    4. \(\frac{7}{10}\)

    5. \(-\frac{1}{14}\)

    6. \(-\frac{1}{4}\)

    7. \(\frac{1}{3}\)

    8. \(-\frac{1}{3}\)

    9. \(\frac{1}{2}\)

    10. \(\frac{1}{48}\)

    11. \(-\frac{1}{63}\)

    12. \(-\frac{1}{30}\)

    13. \(-\frac{25}{7}\) / \(-3\frac{4}{7}\)

    14. \(-\frac{65}{6}\) / \(-10\frac{5}{6}\)

    15. \(\frac{85}{14}\) / \(6\frac{1}{14}\)

    16. \(-\frac{33}{14}\) / \(-2\frac{5}{14}\)

    17. \(-\frac{5}{4}\) / \(-1\frac{1}{4}\)

    18. \(\frac{25}{18}\) / \(1\frac{7}{18}\)

    Answers

    1. \(-\frac{3}{2}\)

    * Use model problem #2 as your guide to convert mixed numbers, find diagonal factor pairs, and cross-cancel. 6-Problem Practice Sheet

    Fraction Multiplication Quiz (Questions 6–10)

    Name: Questions 9 & 10 contain mixed numbers

    Q6 \(\displaystyle {-\frac{6}{25} \times \frac{15}{16} =}\)

    Answer:

    Diagonal 1: (6 & 16) GCF:

    Factors of 6:

    Factors of 16:

    Cross-reduce? [   ] Yes [   ] No

    Diagonal 2: (15 & 25) GCF:

    Factors of 15:

    Factors of 25:

    Cross-reduce? [   ] Yes [   ] No

    Cross-Cancel & Show Work:

    Q7 \(\displaystyle {-\frac{14}{15} \times \left(-\frac{5}{21}\right) =}\)

    Answer:

    Diagonal 1: (14 & 21) GCF:

    Factors of 14:

    Factors of 21:

    Cross-reduce? [   ] Yes [   ] No

    Diagonal 2: (5 & 15) GCF:

    Factors of 5:

    Factors of 15:

    Cross-reduce? [   ] Yes [   ] No

    Cross-Cancel & Show Work:

    Q8 \(\displaystyle {\frac{7}{10} \times \frac{5}{11} =}\)

    Answer:

    Diagonal 1: (7 & 11) GCF:

    Factors of 7:

    Factors of 11:

    Cross-reduce? [   ] Yes [   ] No

    Diagonal 2: (5 & 10) GCF:

    Factors of 5:

    Factors of 10:

    Cross-reduce? [   ] Yes [   ] No

    Cross-Cancel & Show Work:

    Q9 \(\displaystyle {-1\frac{1}{5} \times \frac{5}{9} =}\) Improper:

    Answer:

    Diagonal 1: (6 & 9) GCF:

    Factors of 6:

    Factors of 9:

    Cross-reduce? [   ] Yes [   ] No

    Diagonal 2: (5 & 5) GCF:

    Factors of 5:

    Factors of 5:

    Cross-reduce? [   ] Yes [   ] No

    Cross-Cancel & Show Work:

    Q10 \(\displaystyle {1\frac{7}{8} \times \left(-1\frac{1}{5}\right) =}\) Improper:

    Answer:

    Diagonal 1: (15 & 5) GCF:

    Factors of 15:

    Factors of 5:

    Cross-reduce? [   ] Yes [   ] No

    Diagonal 2: (6 & 8) GCF:

    Factors of 6:

    Factors of 8:

    Cross-reduce? [   ] Yes [   ] No

    Cross-Cancel & Show Work:

    * Make sure all signs (\(+\) or \(-\)) and simplest fraction forms are accurately shown. Page 2 of 3

    Part 2: Integer Multiplication & Mixed Number Reference

    Determine the sign of integer products, then study the mixed number transformation guide.

    Name: Q11–Q15: 4 pts each

    Questions 11–15: Determine whether each integer product is POSITIVE or NEGATIVE, then solve. Check exactly one box per question

    Q11 \((-8) \times (-7)\)

    Sign of final answer:

    [   ] Positive (+) [   ] Negative (−)

    Product:

    Q12 \(9 \times (-6)\)

    Sign of final answer:

    [   ] Positive (+) [   ] Negative (−)

    Product:

    Q13 \((-7) \times 5\)

    Sign of final answer:

    [   ] Positive (+) [   ] Negative (−)

    Product:

    Q14 \((-6) \times (-4)\)

    Sign of final answer:

    [   ] Positive (+) [   ] Negative (−)

    Product:

    Q15 \(8 \times (-3)\)

    Sign of final answer:

    [   ] Positive (+) [   ] Negative (−)

    Product:

    Scratch Work / Notes

    Solution Guide How to Solve a Mixed Number Multiplication Problem

    Problem: \(\displaystyle {1\frac{2}{3} \times \left(-2\frac{1}{4}\right)}\)

    Complete Mathematical Transformation: Problem → Improper → Cross-Reduced → Final Answer

    1. Original Problem

    \(\displaystyle {1\frac{2}{3} \times \left(-2\frac{1}{4}\right)}\)

    2. Improper Fractions

    \(\displaystyle {\frac{5}{3} \times \left(-\frac{9}{4}\right)}\)

    3. Cross-Cancel (\(\div 3\))

    \(\displaystyle {\frac{5}{\mathbf{1}} \times \left(-\frac{\mathbf{3}}{4}\right)}\)

    4. Final Answer

    \(\displaystyle {-\frac{15}{4} = \mathbf{-3\frac{3}{4}}}\)

    1 Convert to Improper Fractions

    Multiply denominator by whole number, add numerator. Keep the negative sign outside!

    \(1\frac{2}{3} = \frac{(1 \times 3) + 2}{3} = \mathbf{\frac{5}{3}}\)

    \(-2\frac{1}{4} = -\frac{(2 \times 4) + 1}{4} = \mathbf{-\frac{9}{4}}\)

    Becomes: \(\mathbf{\frac{5}{3} \times \left(-\frac{9}{4}\right)}\)

    2 Determine Product Sign

    Apply Part 2 integer multiplication rules to set the correct sign upfront.

    \(\text{Positive} \times \text{Negative} = \mathbf{\text{Negative}}\)

    One negative factor means the final answer must have a minus sign (−).

    Sign: \(\mathbf{-}\)

    3 List Factor Pairs & Cross-Cancel

    Check both diagonals to see if any diagonal pair shares a \(\text{GCF} > 1\).

    Diagonal (9 & 3): \(\text{GCF} = 3\). Cross-reduce: \(9 \div 3 = \mathbf{3}\); \(3 \div 3 = \mathbf{1}\).

    Diagonal (5 & 4): \(\text{GCF} = 1\). Cannot reduce! (Keep 5 & 4).

    4 Multiply Straight Across

    Multiply reduced numerators and denominators. Convert improper to mixed number.

    \(\frac{5}{1} \times \left(-\frac{3}{4}\right) = -\frac{5 \times 3}{1 \times 4} = \mathbf{-\frac{15}{4}}\)

    Division: \(15 \div 4 = 3\text{ R }3 \rightarrow \mathbf{-3\frac{3}{4}}\)

    Becomes: \(\mathbf{-3\frac{3}{4}}\)  or  \(\mathbf{-\frac{15}{4}}\)

    Key Rule: Convert mixed numbers to improper fractions before cross-cancelling or multiplying! Keep this reference handy

    * Total Test: 10 Fraction Problems (8 pts each = 80 pts) + 5 Integer Problems (4 pts each = 20 pts) = 100 Points. Page 3 of 3

    Answer: \(\mathbf{\frac{3}{10}}\)

    Diagonal 1: (9 & 15) GCF: 3

    9: 1 × 9, 3 × 3

    15: 1 × 15, 3 × 5

    Cross-reduce? [✓] Yes (\(\div 3 \rightarrow 3, 5\))

    Diagonal 2: (8 & 16) GCF: 8

    8: 1 × 8, 2 × 4

    16: 1 × 16, 2 × 8, 4 × 4

    Cross-reduce? [✓] Yes (\(\div 8 \rightarrow 1, 2\))

    Cross-Cancel & Solution:

    \(\frac{3}{2} \times \frac{1}{5} = \frac{3}{10}\)

    * Diagnostic Check: Question 4 tests student awareness that \(\text{GCF}=1\) means no reduction occurs on that diagonal. Page 1 of 3

    Fraction Multiplication Quiz Answer Key (Questions 6–10)

    Mixed Number Solutions on Q9 & Q10

    Q6 \(\displaystyle {-\frac{6}{25} \times \frac{15}{16} =}\)

    Answer: \(\mathbf{-\frac{9}{40}}\)

    Diagonal 1: (6 & 16) GCF: 2

    6: 1 × 6, 2 × 3

    16: 1 × 16, 2 × 8, 4 × 4

    Cross-reduce? [✓] Yes (\(\div 2 \rightarrow 3, 8\))

    Diagonal 2: (15 & 25) GCF: 5

    15: 1 × 15, 3 × 5

    25: 1 × 25, 5 × 5

    Cross-reduce? [✓] Yes (\(\div 5 \rightarrow 3, 5\))

    Cross-Cancel & Solution:

    \(-\frac{3}{5} \times \frac{3}{8} = -\frac{9}{40}\)

    Q7 \(\displaystyle {-\frac{14}{15} \times \left(-\frac{5}{21}\right) =}\)

    Answer: \(\mathbf{\frac{2}{9}}\)

    Diagonal 1: (14 & 21) GCF: 7

    14: 1 × 14, 2 × 7

    21: 1 × 21, 3 × 7

    Cross-reduce? [✓] Yes (\(\div 7 \rightarrow 2, 3\))

    Diagonal 2: (5 & 15) GCF: 5

    5: 1 × 5

    15: 1 × 15, 3 × 5

    Cross-reduce? [✓] Yes (\(\div 5 \rightarrow 1, 3\))

    Cross-Cancel & Solution:

    \(-\frac{2}{3} \times \left(-\frac{1}{3}\right) = +\frac{2}{9}\)

    Q8 \(\displaystyle {\frac{7}{10} \times \frac{5}{11} =}\)

    Answer: \(\mathbf{\frac{7}{22}}\)

    Diagonal 1: (7 & 11) GCF: 1

    7: 1 × 7

    11: 1 × 11

    Cross-reduce? [✓] No (\(\text{GCF}=1\), keep 7 & 11)

    Diagonal 2: (5 & 10) GCF: 5

    5: 1 × 5

    10: 1 × 10, 2 × 5

    Cross-reduce? [✓] Yes (\(\div 5 \rightarrow 1, 2\))

    Cross-Cancel & Solution:

    \(\frac{7}{2} \times \frac{1}{11} = \frac{7}{22}\)

    Q9 \(\displaystyle {-1\frac{1}{5} \times \frac{5}{9} =}\) Improper: \(-\frac{6}{5}\)

    Answer: \(\mathbf{-\frac{2}{3}}\)

    Diagonal 1: (6 & 9) GCF: 3

    6: 1 × 6, 2 × 3

    9: 1 × 9, 3 × 3

    Cross-reduce? [✓] Yes (\(\div 3 \rightarrow 2, 3\))

    Diagonal 2: (5 & 5) GCF: 5

    5: 1 × 5

    5: 1 × 5

    Cross-reduce? [✓] Yes (\(\div 5 \rightarrow 1, 1\))

    Cross-Cancel & Solution:

    \(-\frac{2}{1} \times \frac{1}{3} = -\frac{2}{3}\)

    Q10 \(\displaystyle {1\frac{7}{8} \times \left(-1\frac{1}{5}\right) =}\) Improper: \(\frac{15}{8} \times \left(-\frac{6}{5}\right)\)

    Answer: \(\mathbf{-\frac{9}{4}}\) or \(\mathbf{-2\frac{1}{4}}\)

    Diagonal 1: (15 & 5) GCF: 5

    15: 1 × 15, 3 × 5

    5: 1 × 5

    Cross-reduce? [✓] Yes (\(\div 5 \rightarrow 3, 1\))

    Diagonal 2: (6 & 8) GCF: 2

    6: 1 × 6, 2 × 3

    8: 1 × 8, 2 × 4

    Cross-reduce? [✓] Yes (\(\div 2 \rightarrow 3, 4\))

    Cross-Cancel & Solution:

    \(\frac{3}{4} \times \left(-\frac{3}{1}\right) = -\frac{9}{4} = -2\frac{1}{4}\)

    * Answers may be expressed as improper fractions or mixed numbers; both are mathematically equivalent. Page 2 of 3

    Answer Key: Integer Sign Rules & Mixed Number Reference

    Solutions for integer multiplication sign checks and the pedagogical worked guide.

    Q11–Q15: 4 pts each

    Questions 11–15 Solutions: Single-digit integer products and sign determinations. 2 pts for correct sign + 2 pts for correct value

    Q11 \((-8) \times (-7)\)

    Sign of final answer:

    [✓] Positive (+) [   ] Negative (−)

    Product: \(\mathbf{+56}\)

    Q12 \(9 \times (-6)\)

    Sign of final answer:

    [   ] Positive (+) [✓] Negative (−)

    Product: \(\mathbf{-54}\)

    Q13 \((-7) \times 5\)

    Sign of final answer:

    [   ] Positive (+) [✓] Negative (−)

    Product: \(\mathbf{-35}\)

    Q14 \((-6) \times (-4)\)

    Sign of final answer:

    [✓] Positive (+) [   ] Negative (−)

    Product: \(\mathbf{+24}\)

    Q15 \(8 \times (-3)\)

    Sign of final answer:

    [   ] Positive (+) [✓] Negative (−)

    Product: \(\mathbf{-24}\)

    Scoring Guidelines (Q11–Q15):

    • Sign Identification: 2 pts

    • Correct Product: 2 pts

    4 pts each • 20 pts total

    Solution Guide Pedagogical Framework: Mixed Number Cross-Cancellation

    Example: \(\displaystyle {1\frac{2}{3} \times \left(-2\frac{1}{4}\right)}\)

    Complete Mathematical Transformation: Problem → Improper → Cross-Reduced → Final Answer

    1. Original Problem

    \(\displaystyle {1\frac{2}{3} \times \left(-2\frac{1}{4}\right)}\)

    2. Improper Fractions

    \(\displaystyle {\frac{5}{3} \times \left(-\frac{9}{4}\right)}\)

    3. Cross-Cancel (\(\div 3\))

    \(\displaystyle {\frac{5}{\mathbf{1}} \times \left(-\frac{\mathbf{3}}{4}\right)}\)

    4. Final Answer

    \(\displaystyle {-\frac{15}{4} = \mathbf{-3\frac{3}{4}}}\)

    1 Convert to Improper Fractions

    Common error: Multiplying whole numbers together. Ensure students convert mixed numbers to improper fractions before reducing.

    \(1\frac{2}{3} = \frac{(1 \times 3) + 2}{3} = \mathbf{\frac{5}{3}}\)

    \(-2\frac{1}{4} = -\frac{(2 \times 4) + 1}{4} = \mathbf{-\frac{9}{4}}\)

    Becomes: \(\mathbf{\frac{5}{3} \times \left(-\frac{9}{4}\right)}\)

    2 Determine Product Sign

    Connecting Part 2 integer rules to fractions: count negative factors first to prevent sign drops in the final answer.

    \(\text{Positive} \times \text{Negative} = \mathbf{\text{Negative}}\)

    One negative factor means the final answer must have a minus sign (−).

    Sign: \(\mathbf{-}\)

    3 List Factor Pairs & Cross-Cancel

    Highlighting both reducible and non-reducible diagonals so students don't force cross-cancellation where GCF = 1.

    Diagonal (9 & 3): \(\text{GCF} = 3\). Cross-reduce: \(9 \div 3 = \mathbf{3}\); \(3 \div 3 = \mathbf{1}\).

    Diagonal (5 & 4): \(\text{GCF} = 1\). Cannot reduce! (Keep 5 & 4).

    4 Multiply Straight Across

    Multiply reduced numerators and denominators. Accept either improper fraction or mixed number.

    \(\frac{5}{1} \times \left(-\frac{3}{4}\right) = -\frac{5 \times 3}{1 \times 4} = \mathbf{-\frac{15}{4}}\)

    Division: \(15 \div 4 = 3\text{ R }3 \rightarrow \mathbf{-3\frac{3}{4}}\)

    Accepted: \(\mathbf{-3\frac{3}{4}}\)  or  \(\mathbf{-\frac{15}{4}}\)

    Teacher Note: Emphasize that cross-cancelling keeps numbers small so students don't need large division algorithms at the end! Scoring Complete

    * Total Test: 10 Fraction Problems (8 pts each = 80 pts) + 5 Integer Problems (4 pts each = 20 pts) = 100 Points. Page 3 of 3

    ?

    3. Whole Number

    \( 8 \)

    Reciprocal:

    ?

    4. Improper Fraction

    \( \frac{11}{3} \)

    Reciprocal:

    ?

    Self-Check Test: Multiply your answer by the original number. If it equals 1, your reciprocal is correct!


    Worked Example

    From Division to Cross-Cancelling

    Complete Problem

    Problem \( \frac{4}{9} \div \frac{8}{15} \)

    Evaluate & simplify fully

    1 Apply KCF

    Multiply by the reciprocal of \( \frac{8}{15} \):

    \( \frac{4}{9} \times \frac{15}{8} \)

    2 Cross Cancel!

    Reduce diagonal factor pairs:

    4 & 8 \( \div 4 \rightarrow \) 1 & 2

    15 & 9 \( \div 3 \rightarrow \) 5 & 3

    3 Multiply Across

    Multiply simplified numbers:

    \( \frac{1 \times 5}{3 \times 2} = \frac{5}{6} \)

    Notice how our previous cross-cancelling skills plug straight in once we flip to multiplication!


    Class Practice

    Try It: Keep • Change • Flip

    Your Turn

    Problem A Two Fractions

    \( \frac{5}{6} \div \frac{2}{3} \)

    Solve on your whiteboard or paper. Simplify completely!

    Problem B With a Whole Number

    \( \frac{7}{10} \div 14 \)

    Solve on your whiteboard or paper. Simplify completely!

    Strategy Checklist: 1. Keep the first • 2. Change to multiply • 3. Flip to the reciprocal • 4. Cross-cancel!

    Cancel 5 & 5 (1, 1); 4 & 6 (2, 3)
    \(= -\frac{1 \times 3}{2 \times 1} = \mathbf{-\frac{3}{2}\text{ or }-1\frac{1}{2}}\)

    1. Ans: \(-\frac{9}{4}\) or \(-2\frac{1}{4}\)

    \(\displaystyle {\frac{12}{5} \times \left(-\frac{15}{16}\right)}\)

    Cancel 12 & 16 (3, 4); 5 & 15 (1, 3)
    \(= -\frac{3 \times 3}{1 \times 4} = \mathbf{-\frac{9}{4}\text{ or }-2\frac{1}{4}}\)

    1. Ans: \(\frac{3}{2}\) or \(1\frac{1}{2}\)

    \(\displaystyle {-\frac{10}{3} \times \left(-\frac{9}{20}\right)}\)

    Cancel 10 & 20 (1, 2); 3 & 9 (1, 3)
    \(= \frac{1 \times 3}{1 \times 2} = \mathbf{\frac{3}{2}\text{ or }1\frac{1}{2}}\)

    Answers

    1. \(\frac{3}{2}\) / \(1\frac{1}{2}\)

    2. \(-\frac{2}{3}\)

    3. \(\frac{5}{4}\) / \(1\frac{1}{4}\)

    4. \(-\frac{7}{10}\)

    5. \(-\frac{3}{2}\) / \(-1\frac{1}{2}\)

    6. \(\frac{8}{15}\)

    7. \(\frac{2}{3}\)

    8. \(-\frac{1}{24}\)

    9. \(-\frac{15}{2}\) / \(-7\frac{1}{2}\)

    10. \(-\frac{3}{2}\) / \(-1\frac{1}{2}\)

    11. \(-\frac{9}{4}\) / \(-2\frac{1}{4}\)

    12. \(\frac{3}{2}\) / \(1\frac{1}{2}\)

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