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MathsAges 10-12

Missing-value equations

Find the missing value that makes an equation true, then check by substitution. Review suitability for your learners before teaching.

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Age band:Ages 7-9Ages 10-12

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Worksheet StudioPractice pack · Ages 10-12

Missing-value equations

Take your time. Show your thinking.

  1. 1. 3 × x + 8 = 17. Find x.

    LHS=RHS
    3 · 8 · 17 · Missing-value equations

  2. 2. 7 × x + 4 = 53. Find x.

    LHS=RHS
    7 · 4 · 53 · Missing-value equations

  3. 3. 12 × x + 13 = 157. Find x.

    LHS=RHS
    12 · 13 · 157 · Missing-value equations

  4. 4. 2 × x + 13 = 17. Find x.

    LHS=RHS
    2 · 13 · 17 · Missing-value equations

  5. 5. 4 × x + 11 = 27. Find x.

    LHS=RHS
    4 · 11 · 27 · Missing-value equations

  6. 6. 4 × x + 18 = 34. Find x.

    LHS=RHS
    4 · 18 · 34 · Missing-value equations

  7. 7. 11 × x + 16 = 137. Find x.

    LHS=RHS
    11 · 16 · 137 · Missing-value equations

  8. 8. 11 × x + 3 = 124. Find x.

    LHS=RHS
    11 · 3 · 124 · Missing-value equations

  9. 9. 7 × x + 18 = 67. Find x.

    LHS=RHS
    7 · 18 · 67 · Missing-value equations

  10. 10. 12 × x + 16 = 160. Find x.

    LHS=RHS
    12 · 16 · 160 · Missing-value equations

  11. 11. 3 × x + 6 = 15. Find x.

    LHS=RHS
    3 · 6 · 15 · Missing-value equations

  12. 12. 10 × x + 15 = 115. Find x.

    LHS=RHS
    10 · 15 · 115 · Missing-value equations
12 questions · Seed 52 · Age guidance, not curriculum certification
View the answer key
Worksheet StudioAnswer key · Ages 10-12

Missing-value equations

Answers and reasoning. Review before teaching.

  1. 1. 3 × x + 8 = 17. Find x.

    3

    Subtract 8, then divide by 3: x = 3.

  2. 2. 7 × x + 4 = 53. Find x.

    7

    Subtract 4, then divide by 7: x = 7.

  3. 3. 12 × x + 13 = 157. Find x.

    12

    Subtract 13, then divide by 12: x = 12.

  4. 4. 2 × x + 13 = 17. Find x.

    2

    Subtract 13, then divide by 2: x = 2.

  5. 5. 4 × x + 11 = 27. Find x.

    4

    Subtract 11, then divide by 4: x = 4.

  6. 6. 4 × x + 18 = 34. Find x.

    4

    Subtract 18, then divide by 4: x = 4.

  7. 7. 11 × x + 16 = 137. Find x.

    11

    Subtract 16, then divide by 11: x = 11.

  8. 8. 11 × x + 3 = 124. Find x.

    11

    Subtract 3, then divide by 11: x = 11.

  9. 9. 7 × x + 18 = 67. Find x.

    7

    Subtract 18, then divide by 7: x = 7.

  10. 10. 12 × x + 16 = 160. Find x.

    12

    Subtract 16, then divide by 12: x = 12.

  11. 11. 3 × x + 6 = 15. Find x.

    3

    Subtract 6, then divide by 3: x = 3.

  12. 12. 10 × x + 15 = 115. Find x.

    10

    Subtract 15, then divide by 10: x = 10.

12 questions · Seed 52 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 10-12

Missing-value equations

Take your time. Show your thinking.

  1. 1. 3 × x + 8 = 17. Find x.

    LHS=RHS
    3 · 8 · 17 · Missing-value equations

  2. 2. 7 × x + 4 = 53. Find x.

    LHS=RHS
    7 · 4 · 53 · Missing-value equations

  3. 3. 12 × x + 13 = 157. Find x.

    LHS=RHS
    12 · 13 · 157 · Missing-value equations

  4. 4. 2 × x + 13 = 17. Find x.

    LHS=RHS
    2 · 13 · 17 · Missing-value equations

  5. 5. 4 × x + 11 = 27. Find x.

    LHS=RHS
    4 · 11 · 27 · Missing-value equations

  6. 6. 4 × x + 18 = 34. Find x.

    LHS=RHS
    4 · 18 · 34 · Missing-value equations

  7. 7. 11 × x + 16 = 137. Find x.

    LHS=RHS
    11 · 16 · 137 · Missing-value equations

  8. 8. 11 × x + 3 = 124. Find x.

    LHS=RHS
    11 · 3 · 124 · Missing-value equations

  9. 9. 7 × x + 18 = 67. Find x.

    LHS=RHS
    7 · 18 · 67 · Missing-value equations

  10. 10. 12 × x + 16 = 160. Find x.

    LHS=RHS
    12 · 16 · 160 · Missing-value equations

  11. 11. 3 × x + 6 = 15. Find x.

    LHS=RHS
    3 · 6 · 15 · Missing-value equations

  12. 12. 10 × x + 15 = 115. Find x.

    LHS=RHS
    10 · 15 · 115 · Missing-value equations
12 questions · Seed 52 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 10-12

Missing-value equations

Answers and reasoning. Review before teaching.

  1. 1. 3 × x + 8 = 17. Find x.

    3

    Subtract 8, then divide by 3: x = 3.

  2. 2. 7 × x + 4 = 53. Find x.

    7

    Subtract 4, then divide by 7: x = 7.

  3. 3. 12 × x + 13 = 157. Find x.

    12

    Subtract 13, then divide by 12: x = 12.

  4. 4. 2 × x + 13 = 17. Find x.

    2

    Subtract 13, then divide by 2: x = 2.

  5. 5. 4 × x + 11 = 27. Find x.

    4

    Subtract 11, then divide by 4: x = 4.

  6. 6. 4 × x + 18 = 34. Find x.

    4

    Subtract 18, then divide by 4: x = 4.

  7. 7. 11 × x + 16 = 137. Find x.

    11

    Subtract 16, then divide by 11: x = 11.

  8. 8. 11 × x + 3 = 124. Find x.

    11

    Subtract 3, then divide by 11: x = 11.

  9. 9. 7 × x + 18 = 67. Find x.

    7

    Subtract 18, then divide by 7: x = 7.

  10. 10. 12 × x + 16 = 160. Find x.

    12

    Subtract 16, then divide by 12: x = 12.

  11. 11. 3 × x + 6 = 15. Find x.

    3

    Subtract 6, then divide by 3: x = 3.

  12. 12. 10 × x + 15 = 115. Find x.

    10

    Subtract 15, then divide by 10: x = 10.

12 questions · Seed 52 · Age guidance, not curriculum certification