Solved Exercises on Money Word Problems in Grade 3

Master money calculations: coin values, addition, subtraction, and real-world money applications through these 5 detailed exercises.

Solution: Exercises 1 to 3
1 Counting Coins
Exercise 1
Sarah has 3 quarters, 2 dimes, and 5 pennies. How much money does she have?
Definition:

Coin Values: Penny = 1¢, Nickel = 5¢, Dime = 10¢, Quarter = 25¢

Coin counting method:
  1. Identify the value of each type of coin
  2. Count how many of each coin you have
  3. Multiply the number of coins by their value
  4. Add all the amounts together
Quarters
3 × 25¢ = 75¢
Dimes
2 × 10¢ = 20¢
Pennies
5 × 1¢ = 5¢
Step 1: Calculate value of quarters

Sarah has 3 quarters: 3 × 25¢ = 75¢

Step 2: Calculate value of dimes

Sarah has 2 dimes: 2 × 10¢ = 20¢

Step 3: Calculate value of pennies

Sarah has 5 pennies: 5 × 1¢ = 5¢

Step 4: Add all amounts together

75¢ + 20¢ + 5¢ = 100¢ = $1.00

🪙
3 quarters = 75¢
dime
2 dimes = 20¢
penny
5 pennies = 5¢
Total = 75¢ + 20¢ + 5¢ = 100¢ = $1.00
Final answer:

Sarah has $1.00

Applied rules:

• Value Recognition: Know the value of each coin (quarter = 25¢)

• Multiplication: Number of coins × value per coin

• Addition: Sum all values to get total amount

• Conversion: 100 cents = 1 dollar

2 Making Change
Exercise 2
Emma buys a toy that costs $2.35. She pays with a $5 bill. How much change should she get back?
Definition:

Change Calculation: Change = Amount Paid - Cost of Item

Amount Paid
$5.00
Cost
$2.35
Change
$5.00 - $2.35 = $2.65
Step 1: Write amounts in decimal form

$5.00 and $2.35

Step 2: Subtract to find change

$5.00 - $2.35 = $2.65

Step 3: Verify the calculation

$2.35 + $2.65 = $5.00 ✓

💰
Paid: $5.00
🛒
Cost: $2.35
💵
Change: $2.65
$5.00 - $2.35 = $2.65
Final answer:

Emma should get $2.65 in change

Applied rules:

• Subtraction: Amount paid minus cost equals change

• Decimal Alignment: Align decimal points when subtracting

• Verification: Add change to cost to verify total payment

3 Comparing Prices
Exercise 3
Jake has $3.50. He wants to buy a book for $2.75 and a pencil for $0.85. Does he have enough money?
Definition:

Total Cost: Add all item prices together

Book Cost
$2.75
Pencil Cost
$0.85
Total Cost
$2.75 + $0.85 = $3.60
Step 1: Add the cost of all items

$2.75 + $0.85 = $3.60

Step 2: Compare with available money

Jake has $3.50, but needs $3.60

Step 3: Determine if he has enough

$3.50 < $3.60, so he does NOT have enough money

📖
Book: $2.75
✏️
Pencil: $0.85
💰
Total: $3.60
$3.50 < $3.60, so Jake does NOT have enough money
Final answer:

No, Jake does not have enough money. He needs $0.10 more.

Applied rules:

• Addition: Add all purchase amounts to find total cost

• Comparison: Compare available money with total cost

• Decision Making: Determine if sufficient funds are available

Money Values and Methods
1 quarter = 25¢, 1 dime = 10¢, 1 nickel = 5¢, 1 penny = 1¢
Coin Values
Counting Method
Number × Value = Total Value
Multiply coins by their value
Change Method
Paid - Cost = Change
Subtract cost from payment
Total Cost
Item₁ + Item₂ = Total
Add all item prices
🪙
Quarter = 25¢
dime
Dime = 10¢
nickel
Nickel = 5¢
penny
Penny = 1¢
Solution: Exercises 4 to 5
4 Budget Planning
Exercise 4
Mia saves $1.25 each week. After 4 weeks, she spends $3.75 on a game. How much money does she have left?
Definition:

Accumulated Savings: Weekly savings × Number of weeks

Weekly Savings
$1.25
Weeks Saved
4 weeks
Total Savings
$1.25 × 4 = $5.00
Step 1: Calculate total savings after 4 weeks

$1.25 × 4 = $5.00

Step 2: Subtract the amount spent

$5.00 - $3.75 = $1.25

Step 3: Verify the result

$3.75 + $1.25 = $5.00 ✓

💰
Saved: $5.00
🎮
Spent: $3.75
💵
Left: $1.25
$1.25 × 4 - $3.75 = $5.00 - $3.75 = $1.25
Final answer:

Mia has $1.25 left after buying the game

Applied rules:

• Multiplication: Weekly amount × number of weeks

• Subtraction: Total savings minus expenses

• Order of Operations: Multiply before subtracting

5 Sharing Money
Exercise 5
Four friends found $2.00 together. They want to share it equally. How much does each friend get?
Definition:

Equal Sharing: Total amount ÷ Number of people = Share per person

Total Amount
$2.00
Number of Friends
4
Each Gets
$2.00 ÷ 4 = $0.50
Step 1: Convert to cents for easier division

$2.00 = 200¢

Step 2: Divide by number of friends

200¢ ÷ 4 = 50¢

Step 3: Convert back to dollars

50¢ = $0.50

Step 4: Verify the result

$0.50 × 4 = $2.00 ✓

💰
Total: $2.00
👥
4 friends
💵
Each gets: $0.50
$2.00 ÷ 4 = $0.50 per friend
Final answer:

Each friend gets $0.50

Applied rules:

• Division: Total amount divided by number of people

• Conversion: Convert dollars to cents for easier division

• Verification: Multiply share by number of people to check total

Money Problem-Solving Strategies
\(\text{Change} = \text{Paid} - \text{Cost}\)
Making Change
Key definitions:

Coin Values: Penny = 1¢, Nickel = 5¢, Dime = 10¢, Quarter = 25¢

Money Operations: Addition, subtraction, multiplication, division

Real-world Applications: Shopping, saving, budgeting, sharing

Complete methodology:
  1. Read the problem carefully: Identify what is being asked
  2. Find important information: Numbers, amounts, operations needed
  3. Choose the operation: Add, subtract, multiply, or divide
  4. Solve step by step: Follow the mathematical process
  5. Check your answer: Make sure it makes sense
Tip 1: Always convert dollars and cents to the same unit (cents) before calculating.
Tip 2: Draw pictures or use real coins to visualize the problem.
Tip 3: Remember that 100 cents equal 1 dollar ($1.00).
Tip 4: Always check if your answer makes sense in the real world.
Common errors: Forgetting to convert between dollars and cents, miscounting coins, incorrect operation selection.
Practice strategies: Work with real money, practice counting by 5s and 10s, solve daily life scenarios.
Money formulas to know:

• Counting coins: Number × Value = Total value

• Calculating change: Paid - Cost = Change

• Finding total cost: Item₁ + Item₂ + ... = Total cost

• Sharing equally: Total ÷ Number of people = Share per person

• Converting units: 100¢ = $1.00

Questions & Answers

Question: I have trouble remembering the value of each coin. How can I easily remember them?

Answer: Here are some memory tricks for coin values:

  • Penny: P = 1¢ (P is the first letter of "penny")
  • Nickel: Ni = 5¢ (Ni sounds like "nigh-five")
  • Dime: Di = 10¢ (D is for "decimal", and 10¢ is one-tenth of a dollar)
  • Quarter: Q = 25¢ (Q is for "quarter", and a quarter is 25 cents of 100)

You can also remember that quarters are worth the most, then dimes, then nickels, then pennies in value order.

Practice by handling real coins and counting them repeatedly. The more you touch them, the better you'll remember!

Question: My child gets confused when solving money problems with both dollars and cents. What's the best approach?

Answer: The key is to convert everything to the same unit. Here's the recommended approach:

  • Convert dollars to cents: Multiply dollars by 100 to get cents
  • Work entirely in cents: Perform all calculations in cents
  • Convert back if needed: Divide by 100 to get dollars and cents

For example: $2.50 = 250¢, $1.75 = 175¢. Then 250¢ - 175¢ = 75¢ = $0.75.

This eliminates confusion between the dollar and cent symbols and makes calculations consistent.

Question: How do I teach students to check if their money word problem answers make sense?

Answer: Teach students to use "real-world logic checks" to verify their answers:

  • Reasonableness test: Does the answer seem realistic for the situation?
  • Unit check: Are dollars and cents properly formatted?
  • Reverse calculation: Add the change back to the cost to see if it equals payment
  • Estimation check: Round numbers to estimate if the answer is close

For example, if someone pays $5 for a $2 item, they shouldn't get $4 back. This doesn't make sense.

Encourage students to always ask: "Does this answer make sense in the story?"

Comprehensive Summary: Money Word Problems
Key Concepts and Definitions:

Money Word Problems: Real-life situations involving coins and bills that require mathematical operations to solve.

Coin Values: Specific monetary amounts assigned to different coins (penny=1¢, nickel=5¢, dime=10¢, quarter=25¢).

Decimal Notation: Writing money amounts with a dollar sign and decimal point (e.g., $2.50).

Cent Notation: Writing money amounts with a cent sign (e.g., 250¢).

Core Rules and Principles:

• Unit Consistency: Always work with the same units (all cents or all dollars with cents).

• Place Value: Understand the relationship between dollars and cents (100¢ = $1.00).

• Operation Selection: Addition for combining amounts, subtraction for finding differences, multiplication for repeated addition, division for sharing equally.

• Verification: Always check if your answer makes sense in the context of the problem.

Step-by-Step Problem-Solving Method:
  1. Read Carefully: Understand what the problem is asking
  2. Identify Information: Find the numbers and operations needed
  3. Plan Strategy: Decide which mathematical operation(s) to use
  4. Solve Step-by-Step: Show your work clearly
  5. Check Answer: Verify it makes sense in the real world
Tip 1: Draw pictures or use real coins to visualize the problem.
Tip 2: Practice with real-life scenarios like shopping or saving.
Tip 3: Always write your final answer with the correct money format.
Tip 4: Estimate first to check if your exact answer is reasonable.
Common Pitfalls: Misreading decimal places, forgetting to carry over in addition/subtraction, mixing up dollars and cents.
Memorization Aids: Remember that 4 quarters = 1 dollar, 10 dimes = 1 dollar, 20 nickels = 1 dollar.
Key Takeaways for Students:

• Master coin values: Penny (1¢), Nickel (5¢), Dime (10¢), Quarter (25¢)

• Always convert to the same unit before calculating

• Use addition for combining money, subtraction for making change

• Check your work by reversing the operation

• Practice regularly with real-world examples