6.NOS.3 Lesson 2-12-part2 Apply Day · Set B
MASTERY CHECK
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2.12 · Part II

Second Practice Form · Independent Application and Spiral Review

Multiply Decimals · Product

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Name: Date: Period: Learning Goal:
■ ADVANCED CONCEPT ANCHOR: 2.12 · Part II
1Multiplying Decimals
2The Structural Procedure
  1. Multiply the numbers as if they were whole numbers (ignore decimals during multiplication)
  2. Count the total number of decimal places in both factors
  3. Place the decimal point in the product so it has that same total number of decimal places
3Mathematical Word Bank
  • Multiply Decimals (Multiplicar decimales) — Find the product of decimals, then use place value to place the decimal point.
  • Product (Producto) — The answer when you multiply.
  • Decimal point (Punto decimal) — The dot that splits the whole number from the part after it.
  • Estimate (Estimar) — A close answer you get by rounding first.
  • Place value (Valor posicional) — What a digit is worth based on where it sits in a number.
  • Decimal places (Cifras decimales) — How many digits come after the decimal point.
4Watch out
  • A common mistake in Multiply Decimals is counting decimal places from only one factor instead of adding the decimal places from BOTH factors. For example, in 0.4 × 0.06, a student multiplies 4 × 6 = 24, then places the decimal point using just one factor's place count (1 place), writing 0.24 instead of the correct answer: 0.4 has 1 decimal place and 0.06 has 2 decimal places, for a total of 3, so 24 becomes 0.024. Before you submit, count the decimal places in EACH factor separately and add them together — that total is how many decimal places belong in your final answer.
SECTION 1 COMPUTATION & PROCEDURAL FLUENCY [Show Every Step]
  1. 1 MULTIPLE CHOICE

    What is 3.4 × 2.6?

    1. A8.84
    2. B88.4
    3. C0.884
    4. D8.48
    Show each partial product, then add them
  2. 2 MULTIPLE CHOICE

    What is 0.7 × 1.5?

    1. A1.05
    2. B10.5
    3. C0.105
    4. D1.50
    Show each partial product, then add them
  3. 3 MULTIPLE CHOICE

    What is 5.3 × 4?

    1. A21.2
    2. B2.12
    3. C212
    4. D20.12
    Show each partial product, then add them
SECTION 2 REAL-WORLD CONTEXTS & PROBLEM SOLVING [Applications]
  1. 4 MULTIPLE CHOICE

    (Lesson 2.5) A data set runs from a least value of 12 to a greatest value of 30. What is the range?

    1. A18
    2. B30
    3. C12
    4. D21
    Put the data in order
    Work
  2. 5 MULTIPLE CHOICE

    (Lesson 2.5) On a box plot, Q1 = 20 and Q3 = 36. What is the interquartile range?

    1. A16
    2. B56
    3. C28
    4. D36
    Put the data in order
    Work
  3. 6 MULTIPLE CHOICE

    The truck sells 2.5 pounds of fries, and each pound earns $1.20 in profit. What is the total profit? (2.5 × 1.2)

    1. A$3.00
    2. B$30.00
    3. C$0.30
    4. D$3.70
    Show each partial product, then add them
SECTION 3 MATHEMATICAL WRITING & ERROR ANALYSIS [Reasoning & Critique]
  1. 7 OPEN RESPONSE

    A driver buys 9.5 gallons of gas at $3.40 per gallon. Show how to find the total cost. Use estimation to check if your answer is reasonable.

    ✏️ Mathematical Justification & Response
📐 CER MATHEMATICAL PROOF MATRIX (CER 2.0) SMP.3 / Proof & Justification

Writing Task: Justify why your mathematical solution is accurate and complete.

C Claim
State your direct mathematical answer/claim with units.
E Evidence
Cite exact numbers, calculations, dimensions, or graph data.
R Reasoning
Explain the mathematical theorem, property, or definition connecting evidence to claim.
Student Mastery Self-Assessment:
1 · Need More Support
2 · Getting Closer
3 · Got It / Solid
4 · Master / Can Teach It