6.AT.9 Group 2 · Challenge

Practice Set · Part 1

Write and Represent Inequalities

Pick up where we left off

Name: Date: Group:

Where we left off

Our goal: I can write inequalities to represent real-world situations, explain what each part stands for, and build one for a situation I have not seen before.

The big idea: Decide if the boundary number is allowed and which way the values go, then choose the symbol that matches both.

Model to copy — Example · "No less than"

  1. To win a prize, a player must score no less than 25 points. Write an inequality for the score s.
  2. Read the whole phrase: no less than 25
  3. Decide if 25 is included: 25 ✓
  4. Pick the symbol: ≥
  5. Write the inequality: s ≥ 25
  6. s ≥ 25. A score of 25 or more wins a prize.

Start here

You did these with your group. Now do them on your own — the model above is yours to copy.

  1. 1

    Same stepsFinish what the group started. Use the model above, step for step.

    Try it together — then prove it: Clue: "A bag holds fewer than 10 items." Write an inequality for the number of items n. What does "fewer than" mean? Is 10 included? (It means less than. 10 is not included.) Write the inequality. (n < 10) Why is n ≤ 10 wrong for this clue? (n ≤ 10 includes 10. But a bag with 10 items does not hold fewer than 10.)
    Show your work
  2. 2

    Warm restartSolve: 6x = 42

    1. Ax = 7
    2. Bx = 36
    3. Cx = 48
    4. Dx = 252

    How do you know?

  3. 3

    Warm restartSolve: n / 3 = 8

    1. An = 3
    2. Bn = 5
    3. Cn = 11
    4. Dn = 24

    How do you know?

  4. 4

    Warm restartSolve: 9m = 63

    1. Am = 7
    2. Bm = 54
    3. Cm = 72
    4. Dm = 567

    How do you know?

8.4 Small Group · Group 2 · Practice SetPart 1 of 4
6.AT.9 Group 2 · Challenge

Practice Set · Part 2

Write and Represent Inequalities

Keep going

You answered these out loud. Now write them.

Answer, then say how you know — the reason is the part that counts.

  1. 5

    Think it throughWhich speed is NOT possible for the getaway car?

    1. A45 mph
    2. B60 mph
    3. C65 mph
    4. D70 mph

    Why is that the answer?

  2. 6

    Think it throughDoes s ≤ 65 include 65 itself?

    1. ANo — it must be strictly less
    2. BYes — the 'or equal to' part includes 65
    3. COnly if the car stops
    4. DOnly on a highway

    How do you know? Give a second reason as well.

  3. 7

    Think it throughWhich inequality means 'at most 65'?

    1. As ≤ 65
    2. Bs < 65
    3. Cs ≥ 65
    4. Ds > 65

    Explain your thinking. What would have to change for a different choice to be right?

  4. 8

    Back to the modelHow do the words 'at least' and 'at most' change the inequality symbol compared to 'more than' and 'fewer than'?

8.4 Small Group · Group 2 · Practice SetPart 2 of 4
6.AT.9 Group 2 · Challenge

Practice Set · Part 3

Write and Represent Inequalities

Words and reasoning

Word bank · Banco de palabras

Inequality (Desigualdad)Greater than (Mayor que)Less than (Menor que)At least / At most (Al menos / A lo más)Variable (Variable)No more than (No más de)Constraint (Restricción)

Use the words

Fill each blank with a word from the bank.

Explain the thinking

  1. 9

    Find the mistakeAnother student made this exact mistake in this lesson. Explain why it is wrong, then write what they should have done.

    The mistake: A common mistake in Write Inequalities is using a strict symbol (> or <) for a phrase that actually includes the boundary value.
  2. 10

    Say moreHow do the phrases 'at least' and 'at most' change which inequality symbol you choose compared to 'more than' and 'fewer than'?

  3. 11

    Write your ownWrite your own problem about this situation, then solve it and show the answer. The situation: Three balance scales are shown. On two of them the pans hang at different heights, so one side is heavier. On the third the pans are level.

    Show your work
8.4 Small Group · Group 2 · Practice SetPart 3 of 4
6.AT.9 Group 2 · Challenge

Practice Set · Part 4

Write and Represent Inequalities

Show what you know

Last check

These two come from Lesson 8.3. If they are shaky, that is the lesson to revisit — not this one.

  1. 12

    Show what you knowExplain your thinking — Which inequality represents: 'A number n is at least 14'?

    1. An ≥ 14
    2. Bn > 14
    3. Cn ≤ 14
    4. Dn < 14

    Explain your choice.

  2. 13

    From Lesson 8.3Explain your thinking — Solve: w / 8 = 6

    1. Aw = 0.75
    2. Bw = 2
    3. Cw = 14
    4. Dw = 48

    How do you know?

  3. 14

    From Lesson 8.3Check: does 9 work?

    1. AYes — 7 × 9 = 63
    2. BNo — 7 × 9 = 56
    3. CNo — 7 + 9 = 16
    4. DOnly if kits cost $9

    How do you know?

Be honest — this tells your teacher what to do next

I can…Not yetGetting thereGot it
I can write inequalities to represent real-world situations, explain what each part stands for, and build one for a situation I have not seen before.
I can explain why it works: Decide if the boundary number is allowed and which way the values go…
I can justify my answer to a skeptic and connect it to a second strategy or representation.

One question I want to ask my group next time