What do you value?

A business owner must pay a contractor for renovations completed on their store. They can choose either Option 1, using money to pay, or alternatively they can select Option 2, trading goods available in the store as a form of payment to the contractor.

Option 1: $800

Option 2: pants, shoes, hats, and jackets (equivalent to $800)

Which option did you choose? Why?

Record your answer in a format of your choice.

In this learning activity, you will learn about money as a method of measuring value and cash as a form of payment for goods and services.

---

Acknowledgements(Opens in a new window)

Thinking about food

We are talking about food today and working with money as a method of measuring value. Explore the following video, “Where Does Food Come From?” to learn about how we make different types of food.

What new learning happened for you? Record your response and share, if possible.

The friendly number ten at the grocery store

Pretend that you are at the grocery store. Examine the following list of ten items.

How can you estimate, using mental math, the cost of purchasing these ten items?

We can group the prices that add up to ten, as this is considered a friendly number that is easier to add.

To find prices that can add up to ten, we explore the combinations of numbers from the list that add to ten:

5 + 5

6 + 4

7 + 3

8 + 2

9 + 1

We scan our items, and notice that the price of an egg salad sandwich is already $10.

Next, we scan and notice that the cost of honey and croutons are each $5.

So, two groups of $5 or $5 + $5 equals $10.

Next, we notice that the price of soup is $6, the bread is $1, and the cost of scone is $3. Together, these three items add to $10.

Lastly, we notice the apple juice is $2 plus the blueberry jam is $4. The crackers are also $4. This gives us another group of $10.

Altogether, we made 4 groups of $10, which is also stated as:

4 x 10 = $40.

The following chart lists the 4 different groupings that were mentioned above.

There are other ways to arrive at the same answer.

Rearrange the prices of items to groups of $10 in a different way than this example. Record your thoughts using a method of your choice.

Can you find a third way to group the prices of these items into $10?

Five as a friendly number

Another way to quickly add items using mental math is to group the items into $5 amounts. The number five is also considered a friendly number.

Numbers that add up to five are:

1 + 4

2 + 3

Which item prices from the list, when combined together, add up to $5? Record your answers using a method of your choice.

Which did you find easier as a number for using mental math? 5 or 10?

Let’s go grocery shopping!

Examine the list of items Zoey mentioned in the TVO video, “Where Does Food Come From?” from the Action section.

Select at least 10 items to purchase from the following list. Using the prices provided and mental math, estimate and record how much you think the number of items you select will cost all together.

Record your estimates using a method of your choice.

Explain the strategy you used. Calculate the actual cost of the items you chose.

Compare this answer to the estimated total you found using mental math.

Reflection

As you read through these descriptions, which sentence best describes how you are feeling about your understanding of this learning activity? Press the button that is beside this sentence.

Now, record your ideas using a voice recorder, speech-to-text, or writing tool.

Press ‘Discover More’ to extend your skills.

Discover More