6.AT.6c Group 2 · Challenge

Practice Set · Part 1

Write and Evaluate Numerical Expressions with Exponents

Pick up where we left off

Name: Date: Group:

Where we left off

Our goal: I can write numerical expressions from a real situation and evaluate them using the order of operations, including powers, explain what each part stands for, and build one for a situation I have not seen before.

The big idea: Parentheses come first, then powers, then multiply and divide, then add and subtract, so where you put parentheses can change the value.

Model to copy — Example · Split a bill

  1. Seven friends split a bill. They order 4 pizzas at 3² dollars each, plus a $6 delivery fee. Write one expression for each friend's share. Evaluate it.
  2. Write the total bill: 4 × 3² + 6
  3. Put the total in parentheses. Then divide by 7: (4 × 3² + 6) ÷ 7
  4. Find the power first: (4 × 9 + 6) ÷ 7
  5. Work inside the parentheses. Then divide: (36 + 6) ÷ 7 = 42 ÷ 7 = 6
  6. (4 × 3² + 6) ÷ 7 = 6. Each friend pays $6.

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: Each student ticket costs 2³ dollars. Evaluate 2 × 15 + 4 × 20 + 8 × 2³. Find the power. Then do each multiplication. (2³ is 8 → 30 + 80 + 64) Add. What is the total? (30 + 80 + 64 = 174) Why must you find 2³ before you multiply by 8? (The exponent belongs only to the 2. So 8 × 2³ means 8 × 8 = 64, not 8 × 2 × 3.)
    Show your work
  2. 2

    Warm restartWhat is the value of 6²?

    1. A8
    2. B12
    3. C36
    4. D62

    How do you know?

  3. 3

    Warm restartWhat is the value of 4³?

    1. A7
    2. B12
    3. C43
    4. D64

    How do you know?

  4. 4

    Warm restartIn 2⁵, which number is the base and which is the exponent?

    1. ABase 2, exponent 5
    2. BBase 2, exponent 2
    3. CBase 5, exponent 2
    4. DBase 5, exponent 5

    How do you know?

6.4 Small Group · Group 2 · Practice SetPart 1 of 4
6.AT.6c Group 2 · Challenge

Practice Set · Part 2

Write and Evaluate Numerical Expressions with Exponents

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 throughWhat is 2.50 + 1.75(8)?

    1. A4.25
    2. B14.00
    3. C16.50
    4. D34.00

    Why is that the answer?

  2. 6

    Think it throughWhat does the 2.50 represent?

    1. AThe cost of one mile
    2. BA flat base fee charged no matter how far you go
    3. CThe number of miles
    4. DThe tip

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

  3. 7

    Think it throughWhat does the 1.75 represent?

    1. AThe base fee
    2. BThe total cost
    3. CThe number of miles
    4. DThe cost per mile, multiplied by the number of miles

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

  4. 8

    Back to the modelTwo students evaluate 3 + 4 × 2 and get 14 and 11. Which one followed the order of operations, and why does the order have to be agreed on at all?

Sort it again — on paper this time

Write the letter of the group each one belongs in.

A — First: the powerB — Second: multiplyC — Third: add and subtract
6.4 Small Group · Group 2 · Practice SetPart 2 of 4
6.AT.6c Group 2 · Challenge

Practice Set · Part 3

Write and Evaluate Numerical Expressions with Exponents

Words and reasoning

Word bank · Banco de palabras

Numerical expression (Expresión numérica)Evaluate (Evaluar)Order of operations (Orden de las operaciones)Power (Potencia)Base (Base)Exponent (Exponente)Evaluate Expressions (Evaluar expresiones)Variable (Variable)

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 with powers is multiplying the base by the exponent: reading 3² as 3 × 2 = 6 instead of 3 × 3 = 9.
  2. 10

    Say moreWhen you evaluate an expression like 4x² + 3, what order do you follow, and why must you square before you multiply?

  3. 11

    Write your ownWrite your own problem about this situation, then solve it and show the answer. The situation: You are the music producer from the story. Your concert cost is given by the expression 150 + 12s, where s is the number of speakers you rent.

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

Practice Set · Part 4

Write and Evaluate Numerical Expressions with Exponents

Show what you know

Last check

These two come from Lesson 6.3. If they are shaky, that is the lesson to revisit — not this one.

  1. 12

    Show what you knowExplain your thinking — Evaluate 2 × 15 + 8 × 2³.

    1. A94
    2. B124
    3. C150
    4. D736

    Explain your choice.

  2. 13

    From Lesson 6.3Explain your thinking — What is the value of 3⁴?

    1. A12
    2. B34
    3. C64
    4. D81

    How do you know?

  3. 14

    From Lesson 6.3Why does the file grow so quickly?

    1. ABecause 4 MB is already large
    2. BBecause 5 is a big exponent
    3. CBecause the studio records faster each time
    4. DBecause each layer doubles the size instead of adding a fixed amount

    How do you know?

Be honest — this tells your teacher what to do next

I can…Not yetGetting thereGot it
I can write numerical expressions from a real situation and evaluate them using the order of operations, including powers, explain what each part stands for, and build one for a situation I have not seen before.
I can explain why it works: Parentheses come first, then powers, then multiply and divide, then add and subtract…
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