Price Tag Tactics Slides Small Group Lab
Price Tag Tactics
Mastering Percents with Visual Models
Markups
Discounts
Tax & Tips
Today's Mission
Visualize It
Use percent bars and tape diagrams to see how money moves.
Calculate It
Solve real-world shopping problems involving tax, tips, and discounts.
%
The Visual Tool: Percent Bar
A Percent Bar shows the relationship between Percent and Amount.
0% 25% 50% 75% 100%
$0 ? ? ? $80 (Total)
100%
Always the Whole or Original Price
Sections
Equal pieces of the total price
Benchmarks
Use 10%, 25%, or 50% to help!
Strategy 1: Markups (Adding On)
When we add tax or tip, the final amount is more than 100% .
Pizza Night!
Bill: $40 | Tip: 20%
Total = 120%
100% ($40)
20% (Tip)
Start + Add Tip
1
Find 10% of $40 ($4)
2
Double it for 20% ($8)
Final Cost
$48
Strategy 2: Markdowns (Taking Off)
When we use a coupon, the final amount is less than 100% .
Sneaker Sale
Original: $100 | Discount: 25%
Sale = 75%
What You Pay (75%)
Off (25%)
$0 $75 $100 (Orig)
Discount Amount
$25
Sale Price
$75
The Double Play: Multi-Step
Most real shopping has two steps : Discount FIRST, then Tax.
Step 1
The Discount
Calculate the markdown from the original price.
This gives you the Sale Price.
Step 2
The Tax
Calculate tax based on the sale price (not the original!).
This gives you the Final Total.
Tip: Always subtract discounts before adding taxes!
Price Tag Lab Worksheet Price Tag Lab
Solving Multi-Step Percent Problems
Name:
Date:
Part 1: The Markup (Tax & Tip)
Scenario: You and a friend go to lunch. The bill is $30 . You want to leave a 20% tip .
1. Fill in the Percent Bar to find the Tip:
0% 20% 40% 60% 80% 100%
$0 ____ ____ ____ ____ $30
A. What is 20% of $30?
B. What is the Total Bill?
Part 2: The Markdown (Discounts)
Scenario: A video game is originally $60 . Today, it is on sale for 25% off .
2. Divide the Tape Diagram into four 25% sections:
$0 (0%) Total: $60 (100%)
Discount Amount (25%):
New Sale Price:
Part 3: The Multi-Step Challenge
The Scenario: Shopping Spree
You buy a skateboard for $80 .
1. You have a coupon for 10% off .
2. Then, you must pay 5% sales tax on the sale price.
Step 1: Calculate Discount
New Sale Price: $__________
Step 2: Calculate Tax
Final Total: $__________
Part 4: Detective Work (Error Analysis)
Problem: A $50 jacket is marked up by 10% tax.
Student's Work:
10% of $50 = $5
$50 - $5 = $45
Final Answer: $45
What did they do wrong?
How do you fix it?
Price Tag Teacher Guide Teacher Playbook
Lesson: Price Tag Tactics
Standard: CO 7.RP.A.3
Intervention Focus
Target Misconceptions
Operation Confusion: Subtracting tax/tip or adding discounts.
Base Price Error: Calculating multi-step tax on the original price instead of the sale price.
Additive Thinking: Trying to add percents (e.g., 20% off + 10% tax = 10% off).
Guided Questions
"Is the final price going to be more or less than 100%?"
"Which part of our diagram represents the 100% whole?"
"What did the price 'change' to before we added the tax?"
Worksheet Answer Key
Part 1: The Markup
10% of $30: $3.00
20% of $30: $6.00 (The Tip)
Total Bill: $36.00
Note: Students should fill bar with $6 intervals ($0, $6, $12, $18, $24, $30).
Part 2: The Markdown
Division: 4 sections of $15 each.
Discount: $15.00
Sale Price: $45.00
Part 3: Multi-Step Challenge ($80 Skateboard)
Step 1: 10% Discount
10% of $80 = $8
Sale Price = $80 - $8 = $72
Step 2: 5% Sales Tax
(Calculated on $72 sale price)
10% of $72 = $7.20 → 5% = $3.60
Final Total: $75.60
Part 4: Error Analysis
The Error: The student treated "Tax" as a discount. They subtracted the $5 instead of adding it.
The Fix: $50 + $5 = $55. Tax always increases the total.
Progress Check
Tier 3 (1-2 correct)
Approaching (3 correct)
Mastery (All correct)