Cost: The price of an item
Payment: Money given to buy an item
Change: Money returned after purchase
Association: Connection between concepts and ideas
Making change association: Connecting the relationship between cost, payment, and change in a transaction
- Identify the cost of the item ($0.75)
- Identify the payment given ($1.00)
- Subtract cost from payment to find change
- Associate the three elements: cost + change = payment
Cost = $0.75, Payment = $1.00
$1.00 - $0.75 = $0.25
Cost + Change = Payment: $0.75 + $0.25 = $1.00
Sarah gets $0.25 in change. Association: $0.75 + $0.25 = $1.00
• Subtraction: Payment - Cost = Change
• Association rule: Cost + Change = Payment
• Coin value: 1 quarter = $0.25
Multiple coins association: Connecting coin values to their total worth and the change received
2 quarters = 2 × $0.25 = $0.50
$0.50 - $0.45 = $0.05
$0.05 = 1 nickel (association: 5 cents = 1 nickel)
Cost + Change = Payment: $0.45 + $0.05 = $0.50 ✓
Tom receives $0.05 in change (1 nickel). Association: 2 quarters = $0.50, $0.45 + $0.05 = $0.50
• Multiplication: 2 quarters = 2 × $0.25 = $0.50
• Subtraction: $0.50 - $0.45 = $0.05
• Association: $0.05 = 1 nickel
Dollar-cent association: Connecting dollar amounts with cent equivalents in change calculations
Cost = $1.80, Payment = $2.00
$2.00 - $1.80 = $0.20
$0.20 = 20 cents = 2 dimes (association: $0.20 ↔ 20¢ ↔ 2 dimes)
Cost + Change = Payment: $1.80 + $0.20 = $2.00 ✓
Emma gets $0.20 in change (2 dimes). Association: $0.20 = 20¢ = 2 dimes
• Decimal subtraction: $2.00 - $1.80 = $0.20
• Association: $0.20 = 20¢ = 2 dimes
• Verification: $1.80 + $0.20 = $2.00 ✓
Mixed coins association: Connecting different coin combinations that equal the same value
3 quarters = 3 × $0.25 = $0.75
$0.75 - $0.60 = $0.15
$0.15 = 1 dime + 1 nickel OR 3 nickels OR 15 pennies
$0.15 = 1 dime + 1 nickel (association: 10¢ + 5¢ = 15¢)
Alex receives $0.15 in change. Association: $0.15 = 1 dime + 1 nickel
• Multiplication: 3 × $0.25 = $0.75
• Subtraction: $0.75 - $0.60 = $0.15
• Association: $0.15 = 1 dime + 1 nickel
Complex association: Connecting multiple items, total cost, and change in a single transaction
$1.25 + $0.35 = $1.60
$2.00 - $1.60 = $0.40
Item 1 + Item 2 = Total Cost: $1.25 + $0.35 = $1.60
Payment = Total Cost + Change: $2.00 = $1.60 + $0.40
Maya receives $0.40 in change. Association: ($1.25 + $0.35) + $0.40 = $2.00
• Addition: Total cost = $1.25 + $0.35 = $1.60
• Subtraction: $2.00 - $1.60 = $0.40
• Complex association: All parts of transaction connected