Solved Exercises on Money Word Problems Subtraction in Grade 3

Master money word problems subtraction: making change, spending, and comparison through these 5 detailed exercises.

Solution: Exercises 1 to 3
1 Making Change
Exercise 1
Tom bought a toy for $3.75. He paid with a $5.00 bill. How much change should he receive?
Definition:

Making change: Finding the difference between amount paid and cost of item

Subtraction Method:
  1. Identify the amount paid
  2. Identify the cost of the item
  3. Subtract the cost from the amount paid
  4. Align decimal points when subtracting
Amount Paid
$5.00
Cost of Item
-$3.75
Change
$1.25
Step 1: Identify the amount paid

Tom paid $5.00

Step 2: Identify the cost of the item

The toy costs $3.75

Step 3: Set up the subtraction

$5.00 - $3.75

Step 4: Subtract the cents

Since 0 < 5 in the hundredths place, borrow 1 from the tenths place

10 - 5 = 5 cents

Step 5: Subtract the tenths

Since we borrowed, 9 - 7 = 2 tenths

Step 6: Subtract the dollars

4 - 3 = 1 dollar

Step 7: Combine the results

$1.25

Tom should receive $1.25 in change
Final answer:

Tom should receive $1.25 in change

Applied rules:

• Change formula: Amount paid - Cost = Change

• Decimal alignment: Align decimal points when subtracting

• Borrowing: When top digit is smaller, borrow from the next place value

💵
$5.00
Paid
玩具
$3.75
Cost
🪙
$1.25
Change
2 Spending Money
Exercise 2
Sarah had $12.50 in her wallet. She spent $4.25 on lunch. How much money does she have left?
Definition:

Spending money: Finding the remaining amount after money is spent

Starting Amount
$12.50
Amount Spent
-$4.25
Remaining
$8.25
Step 1: Identify the starting amount

Sarah started with $12.50

Step 2: Identify the amount spent

She spent $4.25 on lunch

Step 3: Set up the subtraction

$12.50 - $4.25

Step 4: Subtract the cents

50 - 25 = 25 cents

Step 5: Subtract the dollars

12 - 4 = 8 dollars

Step 6: Combine the results

$8.25

Sarah has $8.25 left
Final answer:

Sarah has $8.25 left

Applied rules:

• Remaining formula: Starting amount - Spent = Left

• Decimal alignment: Align decimal points when subtracting

• Context: Spending reduces the amount of money

$12.50
-
$4.25
=
$8.25
3 Comparison Subtraction
Exercise 3
Emma has $9.75 and Mark has $6.30. How much more money does Emma have than Mark?
Definition:

Comparison subtraction: Finding the difference between two amounts

Emma's Amount
$9.75
Mark's Amount
- $6.30
Difference
$3.45
Step 1: Identify the larger amount

Emma has $9.75 (the larger amount)

Step 2: Identify the smaller amount

Mark has $6.30 (the smaller amount)

Step 3: Set up the subtraction

$9.75 - $6.30

Step 4: Subtract the cents

75 - 30 = 45 cents

Step 5: Subtract the dollars

9 - 6 = 3 dollars

Step 6: Combine the results

$3.45

Emma has $3.45 more than Mark
Final answer:

Emma has $3.45 more than Mark

Applied rules:

• Comparison formula: Larger amount - Smaller amount = Difference

• Decimal alignment: Align decimal points when subtracting

• Context: "How much more" indicates subtraction

👩
$9.75
Emma
❓
More than?
Compare
👨
$6.30
Mark
💰
$3.45
Difference
Money Subtraction Concepts and Rules
Change = Amount Paid - Cost
Making Change Formula
Subtraction Type
Making Change
Payment - Cost
Subtraction Type
Spending
Starting - Spent
Subtraction Type
Comparison
Larger - Smaller
Subtraction Type
Remaining
Original - Used
Key definitions:

Subtraction: Taking away one number from another to find the difference

Change: The money returned when you pay more than the cost

Remaining: What is left after spending or taking away

Difference: The amount between two quantities

Subtraction Method:
  1. Read the problem: Understand what subtraction is being asked for
  2. Identify amounts: Find the larger and smaller amounts
  3. Align decimals: Place decimal points in vertical alignment
  4. Subtract: Begin from rightmost digit and move left
  5. Borrow if needed: When top digit is smaller than bottom digit
  6. Check answer: Verify by adding the difference to the smaller amount
Tip 1: Always align decimal points when subtracting money.
Tip 2: When borrowing, remember that 1 dollar = 100 cents.
Tip 3: Look for clue words like "left," "remaining," "difference," "more than."
Tip 4: Check your answer by adding the difference back to the smaller amount.
Common errors: Misaligning decimals, forgetting to borrow, subtracting smaller from larger incorrectly.
Practice areas: Decimal alignment, borrowing across zeros, making change.
Making Change: Amount paid minus cost of item equals change
Spending: Starting amount minus spent amount equals remaining
Comparison: Larger amount minus smaller amount equals difference
Remaining: Original amount minus used amount equals left over
Remaining = Starting Amount - Amount Spent
Spending Formula
Solution: Exercises 4 to 5
4 Spending from Gift Money
Exercise 4
James received $20.00 for his birthday. He spent $7.85 on books. How much birthday money does he have left?
Definition:

Gift money subtraction: Finding remaining amount after spending gift money

Gift Amount
$20.00
Amount Spent
-$7.85
Remaining
$12.15
Step 1: Identify the gift amount

James received $20.00

Step 2: Identify the amount spent

He spent $7.85 on books

Step 3: Set up the subtraction

$20.00 - $7.85

Step 4: Subtract the cents

Since 0 < 5, borrow from tenths: 10 - 5 = 5 cents

Step 5: Subtract the tenths

Since we borrowed, 9 - 8 = 1 tenth

Step 6: Subtract the dollars

Since we borrowed from tens, 19 - 7 = 12 dollars

Step 7: Combine the results

$12.15

James has $12.15 left
Final answer:

James has $12.15 left

Applied rules:

• Remaining formula: Starting amount - Spent = Left

• Multiple borrowing: May need to borrow from multiple place values

• Decimal alignment: Align decimal points when subtracting

🎁
$20.00
Gift
📚
$7.85
Books
💰
$12.15
Left
5 Savings Comparison
Exercise 5
Maria saved $15.60 for a new toy. Her brother saved $11.25 for the same toy. How much more did Maria save compared to her brother?
Definition:

Savings comparison: Finding the difference between two savings amounts

Maria's Savings
$15.60
Brother's Savings
- $11.25
Difference
$4.35
Step 1: Identify Maria's savings

Maria saved $15.60

Step 2: Identify brother's savings

Her brother saved $11.25

Step 3: Set up the subtraction

$15.60 - $11.25

Step 4: Subtract the cents

Since 0 < 5, borrow from tenths: 10 - 5 = 5 cents

Step 5: Subtract the tenths

Since we borrowed, 5 - 2 = 3 tenths

Step 6: Subtract the dollars

15 - 11 = 4 dollars

Step 7: Combine the results

$4.35

Maria saved $4.35 more than her brother
Final answer:

Maria saved $4.35 more than her brother

Applied rules:

• Comparison formula: Larger amount - Smaller amount = Difference

• Decimal alignment: Align decimal points when subtracting

• Context: "How much more" indicates subtraction

👩
$15.60
Maria
❓
More than?
Compare
👨
$11.25
Brother
💰
$4.35
Difference
Money Word Problems Subtraction Summary
Comprehensive Summary of Money Subtraction Problems
Definitions of Key Concepts:

Subtraction: The mathematical operation of taking one number away from another to find the difference.

Making change: Calculating the money returned when payment exceeds the cost of an item.

Remaining: The amount left after money has been spent or taken away.

Difference: The amount between two quantities found by subtraction.

Comparison: Finding how much more or less one amount is compared to another.

Core Rules and Principles:

• Decimal alignment: Always align decimal points when subtracting money amounts.

• Borrowing rule: When the top digit is smaller than the bottom digit, borrow from the next place value.

• Context matters: Different situations require subtraction but may have different meanings.

• Verification: Check your answer by adding the difference back to the smaller amount.

Step-by-Step Methods:

1. Read the problem: Understand the context and what subtraction represents.

2. Identify amounts: Find the larger and smaller amounts to subtract.

3. Align decimals: Write numbers vertically with decimal points aligned.

4. Subtract column by column: Start from the rightmost digit (cents).

5. Borrow when needed: If top digit is smaller, borrow from the next place value.

6. Check your answer: Verify by adding the difference to the smaller amount.

Examples from Simple to Advanced:

Simple Subtraction: $5.00 - $2.00 = $3.00 (no borrowing needed)

With Borrowing: $5.25 - $1.75 = $3.50 (borrow from tenths)

Complex Borrowing: $10.00 - $3.45 = $6.55 (borrow from multiple places)

Real-world: $25.00 - $18.75 = $6.25 (making change)

Tips and Tricks:

• Clue words: "left," "remaining," "difference," "more than," "less than," "change" indicate subtraction.

• Estimate first: Round numbers to estimate your answer before calculating precisely.

• Check with addition: Add your answer to the smaller number to verify it equals the larger number.

• Visualize: Draw coins or bills to understand the problem better.

Common Pitfalls to Avoid:

• Misaligning decimal points when setting up subtraction

• Forgetting to borrow when the top digit is smaller than the bottom

• Subtracting the smaller number from the larger when it should be the opposite

• Not converting dollars to cents when borrowing across place values

Key Takeaways for Memorization:

• Always align decimal points when subtracting money

• When borrowing, 1 dollar = 100 cents

• "How much more" and "difference" indicate subtraction

• Check your work by adding the difference back to verify

Difference = Larger Amount - Smaller Amount
Comparison Formula
➖
Subtract
Money
.ALIGN
Align
Decimals
🔄
Borrow
When Needed
✅
Check
Answer

Questions & Answers

Question: When do I need to borrow in money subtraction problems?

Answer: You need to borrow when the top digit is smaller than the bottom digit in any place value:

  • In the cents place: If top number < bottom number, borrow from tenths
  • In the tenths place: If top number < bottom number, borrow from dollars
  • In the dollars place: If top number < bottom number, borrow from tens

Example: $5.00 - $2.75 → Need to borrow in both cents and tenths places.

Question: How can I check if my subtraction answer is correct?

Answer: There are two ways to check your subtraction answer:

  • Addition check: Add your answer to the number you subtracted - it should equal the original number
  • Estimation check: Round numbers to estimate if your answer is reasonable

Example: $10.00 - $3.25 = $6.75 → Check: $6.75 + $3.25 = $10.00 ✓

Question: What are some clue words that tell me to use subtraction in money problems?

Answer: Look for these clue words that indicate subtraction:

  • Change scenarios: "change," "returned," "get back"
  • Spending: "spent," "used," "cost," "paid"
  • Remaining: "left," "remaining," "after," "how much is left"
  • Comparison: "more than," "less than," "difference," "how much more"

Always read the full sentence to understand the context!