F. Financial Literacy · Making Change

Change for Two or More Items

F1.1 A1About 40 minutes

Learning goals

I can find the total cost of 2 or 3 items.
I can find the change after buying more than one item.
I can choose a strategy: add first, or take away one price at a time.
I can tell if I have enough money before I buy.

Words to know

total
All the prices added together. A 25¢ cookie and a 40¢ apple have a total of 65¢.

cost
How much you must pay. The cost of 2 items is their total.

enough
As much money as the total, or more.

strategy
A plan or way to solve a problem.

Let's get started!

It is the school Winter Carnival! There is a snack table and a craft table. Most people buy more than one thing. How do the helpers find the change?

Snack table	Price
Cookie	25¢
Popcorn	35¢
Apple	40¢
Maple taffy	45¢
Juice box	50¢
Hot chocolate	60¢

Winter Carnival snack table. Every snack costs less than $1.

Craft table	Price
Bookmark	$1
Button pin	$2
Puzzle	$4
Book	$5
Knitted toque	$6

Winter Carnival craft table. Every price is in whole dollars.

Strategy A: Add first, then find the change

Add the prices to find the total.
Make sure you have enough money.
Count up from the total to the money you paid.

Worked example

Example 1: Two snacks

Lucas buys a cookie (25¢) and an apple (40¢). He pays with a loonie. What is his change?

Add: 25 + 40 = 65¢. That is less than 100¢, so a loonie is enough.
Count up from 65 to 100: 65 to 70 is 5, 70 to 100 is 30. 5 + 30 = 35.
Check: 65 + 35 = 100. ✔

Lucas gets 35¢ in change.

The loonie (100¢) is the whole. The cookie (25¢) and apple (40¢) are two parts. The missing part is the change: 35¢.

Strategy B: Take away one price at a time

You can also subtract each price from the money you paid, one at a time.

For Lucas: 100 − 25 = 75. Then 75 − 40 = 35. The change is 35¢, the same as before!

Worked example

Example 2: Two crafts

Grace buys a book ($5) and a puzzle ($4). She pays with a $10 bill. What is her change?

Add: $5 + $4 = $9.
Change: 9 + 1 = 10, so the change is $1.
Or take away one at a time: $10 − $5 = $5. Then $5 − $4 = $1.

Grace gets $1 in change (a loonie).

Worked example

Example 3: Three items

Eli buys a button pin ($2), a bookmark ($1) and a puzzle ($4). He pays with a $10 bill. What is his change?

Add: $2 + $1 = $3. Then $3 + $4 = $7.
Change: 7 + 3 = 10, so the change is $3.
Check: $7 + $3 = $10. ✔

Eli gets $3 in change.

Worked example

Example 4: Is it enough?

Zoe has a loonie. Can she buy hot chocolate (60¢) and popcorn (35¢)? Can she buy hot chocolate and a juice box (50¢)?

Hot chocolate and popcorn: 60 + 35 = 95¢. 95 is less than 100. Yes! Her change is 5¢.
Hot chocolate and a juice box: 60 + 50 = 110¢. 110 is more than 100. No. She needs 10¢ more.

Zoe can buy hot chocolate and popcorn (change 5¢), but not hot chocolate and a juice box.

Zoe's two shopping plans from Example 4. The dashed line is her loonie. Hot chocolate and popcorn stop before the line. Hot chocolate and juice go past it, so she does not have enough.

Always check the total first

Before you find the change, compare the total with the money you have. If the total is more than your money, you do not have enough, and there is no change to find.

Pick a strategy and stick with it

Both strategies work. Choose the one that feels easier for the numbers. When you finish, check your answer with the other strategy. If you get stuck, take a breath and try a drawing like the bar above.

Just for fun

Why did the cookie and the hot chocolate go to the carnival together?

Because together they make a total treat!

Hands-on activity

Winter carnival at home

You need: sticky notes, 6 to 10 things from around the house, and play money (paper loonies, toonies, $5 and $10 bills, and some coins).

Set up two tables like the carnival. On one, put small things with prices under $1 (ending in 0 or 5). On the other, put things with whole-dollar prices from $1 to $6.
The shopper gets a loonie to spend at the snack table, or a $10 bill to spend at the craft table.
The shopper picks 2 or 3 things and finds the total.
The helper finds the change using Strategy A. The shopper checks with Strategy B.
Write each sale on paper: items, total, money paid, change.

Math talk: "Which strategy did you like better for these numbers? Why?"

Your turn

Buy a cookie and a juice box. Pay with a loonie. What is the total? What is the change?

Buy an apple and popcorn. Pay with a loonie. What is the change?

Buy a bookmark and a book. Pay with a $10 bill. What is the change?

Buy a button pin and a toque. Pay with a $10 bill. What is the change?

Buy 2 cookies. Pay with a loonie. What is the change?

Buy maple taffy and a juice box. Pay with a loonie. What is the change?

Can you buy hot chocolate and maple taffy with a loonie? Explain.

More practice: warm-up

What is 20¢ + 30¢?

What is $3 + $4?

Something costs $7. You pay with a $10 bill. What is the change?

What is 25¢ + 25¢? What is the change from a loonie?

Three items cost $2 each. What is the total? What is the change from $10?

More practice: on your own

Buy an apple, a cookie and popcorn. Pay with a loonie. What is the change?

Buy a puzzle, a button pin and a bookmark. Pay with a $10 bill. What is the change?

Buy popcorn and a cookie with a loonie. Find the change by taking away one price at a time.

Ray wants a toque and a book. He has a $10 bill. Is that enough? If not, what if he pays with a $20 bill?

Buy a juice box and an apple. Pay with a loonie. What is the change?

Challenge

Eva has a loonie. She wants 2 different snacks and exactly 5¢ change. Which 2 snacks could she buy? Find both answers.

Ben buys 3 different crafts with a $10 bill and gets $1 back. Which 3 crafts did he buy?

Lily buys 2 cookies and an apple with a loonie. What is her change? Can she buy anything else from the snack table with her change?

Check your understanding

Quiz

A cookie costs 25¢ and popcorn costs 35¢. What is the total?

You buy the cookie and popcorn (total 60¢) with a loonie. What is your change?

A book is $5 and a button pin is $2. You pay with a $10 bill. What is your change?

You have a loonie. Which can you buy?

You pay $10 for a $4 item and a $3 item. Which shows taking away one price at a time?

You buy items that cost $1, $2 and $4. You pay with a $10 bill. What is your change?

For parents and teachers

What your child is learning: to calculate change when buying more than one item (F1.1), with prices either all in cents (under $1) or all in whole dollars. Two mental math strategies are taught: add the prices first and then count up to the amount paid, or subtract each price from the amount paid one at a time. Children also decide whether they have enough money before working out change. The lesson encourages choosing a strategy and checking with another (A1: mathematical processes and perseverance).

Common difficulties:

Finding the change for only one item and forgetting the other. Ask your child to underline every item in the question.
Adding the money paid to the prices. Ask, "Should the change be more or less than the money you paid?"
Not noticing when the total is more than the money. Always ask, "Is it enough?" first.

How to help: At a store or with a flyer, pick two small items and ask your child for the total and the change from a $10 bill. Keep amounts small (totals up to $10, or up to 100¢).