6.AT.4 Lesson 4-4-group1 🟡 Group 1 · Set B
MASTERY CHECK
☐ Exceeds☐ Meets Target☐ Needs Practice

4.4 Small Group · Group 1

Second Practice Form · Re-Teach, Homework or Retake · Same Standard, New Problems

Percent of a Number · Percent · Procedural Fluency · Real-World Applications

Interactive Workbench & Models →
Name: Date: Period: Learning Goal:
■ CONCEPT SUMMARY & GUIDED NOTES: Let's build it together — How do I find the percent of a number?
1Write the percent as a decimal (move the point 2 places left), then multiply it by the base: part = percent × base.
  • A percent is a piece of a whole. The whole is called the base — it is the number right after the word “of,” and “of” means multiply. Your answer is the piece you get, called the part. We'll walk through a worked example, try one together, then you'll try a few with hints right there when you need them.
2Worked Example — Watch me
  1. The claw machine costs 60 tickets, and it is 25% off. I need 25% of 60.
  2. Step 1 — find the base (the whole): the number after “of” is 60.
  3. Step 2 — the percent as a decimal: 25% means 25 out of 100, so 25 ÷ 100 = 0.25.
  4. Step 3 — multiply: 0.25 × 60 = 15.
  5. The discount is 15 tickets. Check: 15 is about a quarter of 60, so that makes sense.
3Mathematical Word Bank
  • Percent of a Number (Porcentaje de un número) — A part of a number found by multiplying the number by the percent written as a decimal.
  • Percent (Porcentaje) — A way to compare a number to 100, shown with the % sign.
  • Base (Base) — The whole amount you start with — the number right after the word “of.”
  • Part (Parte) — How much of the base (the whole) you get. It is your answer.
  • Equation (Ecuación) — A number sentence with an equal sign. The percent one is: part = percent × base.
  • Discount (Descuento) — Money taken off the first price to make it cheaper.
4Watch out
  • A common mistake in Find the Percent of a Number is multiplying by the percent number itself instead of its decimal form — for example, finding 30% of 80 by computing 30 × 80 = 2,400 instead of 0.30 × 80 = 24. Always divide the percent by 100 to get the decimal, then multiply that decimal by the base.
SECTION 1 REAL-WORLD CONTEXTS & PROBLEM SOLVING [Applications]
  1. 1 MULTIPLE CHOICE

    An arcade prize costs 240 tickets. If you have a coupon for 15% off, how many tickets do you save?

    1. A36 tickets
    2. B24 tickets
    3. C15 tickets
    4. D204 tickets
    0%50%100%
    Work
    1. 1Whole100% is what number?
    2. 2Find 10%Divide by 10.
    3. 3BuildAdd or multiply to the percent.
    4. 4CheckIs it under or over the whole?
  2. 2 MULTIPLE CHOICE

    A student scored 72 out of 90 on a test. What percent did they score?

    1. A80%
    2. B72%
    3. C75%
    4. D90%
    ✏️ Workspace & Solution Steps
  3. 3 MULTIPLE CHOICE

    The claw machine prize is 80 tickets and today it is 25% off. How many tickets do you save?

    1. A20
    2. B25
    3. C55
    4. D16
    0%50%100%
    Work
    1. 1Whole100% is what number?
    2. 2Find 10%Divide by 10.
    3. 3BuildAdd or multiply to the percent.
    4. 4CheckIs it under or over the whole?
  4. 4 MULTIPLE CHOICE

    Your bowling score was 60 points. The bonus round adds 15% more points. How many bonus points is that?

    1. A9
    2. B15
    3. C45
    4. D75
    0%50%100%
    Work
    1. 1Whole100% is what number?
    2. 2Find 10%Divide by 10.
    3. 3BuildAdd or multiply to the percent.
    4. 4CheckIs it under or over the whole?
  5. 5 MULTIPLE CHOICE

    A snack at the arcade costs $40. The sales tax is 5%. How many dollars is the tax?

    1. A$2
    2. B$5
    3. C$8
    4. D$20
    0%50%100%
    Work
    1. 1Whole100% is what number?
    2. 2Find 10%Divide by 10.
    3. 3BuildAdd or multiply to the percent.
    4. 4CheckIs it under or over the whole?
SECTION 2 MATHEMATICAL WRITING & ERROR ANALYSIS [Reasoning & Critique]
  1. 6 ERROR ANALYSIS

    Spot the Common Mistake

    1. 1Find 30% of 80:30% of 80
    2. 2Multiply by the percent number:30 × 80 = 2,400
    3. 3Final answer:30% of 80 = 2,400

    Which step contains the error? Explain the mathematical misconception and write the correct calculation below.

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

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

C Claim
Starter: My mathematical claim is that the solution is...
E Evidence
Starter: The evidence from the model/table demonstrates that...
R Reasoning
Starter: This proves my answer because the standard mathematical definition of...
Student Mastery Self-Assessment:
1 · Need More Support
2 · Getting Closer
3 · Got It / Solid
4 · Master / Can Teach It