Buying things
When you make a purchase, you need to work out the total cost, decide what to pay, and check your change.
Step 1: Find the total cost
Add the prices.
Example: A book for $8.75 and a pen for $2.40.
$8.75 + $2.40 = $11.15
Line up the decimal points when adding money.
Step 2: Sales tax
In Canada, most prices on the shelf don’t include sales tax. The tax is added at the till. Depending on the province, it’s between 5% and 15%. For now, many problems give you the total with tax already included. (You’ll calculate tax yourself in the percent lessons.)
Step 3: Cash rounding
Canada no longer uses pennies. When you pay cash, the total is rounded to the nearest 5 cents:
| Total ends in | Rounds to |
|---|---|
| 1 or 2 cents | 0 (round down) |
| 3 or 4 cents | 5 (round up) |
| 6 or 7 cents | 5 (round down) |
| 8 or 9 cents | 0 (round up) |
$11.13 → $11.15; $11.12 → $11.10; $11.18 → $11.20.
Card payments are not rounded.
Step 4: Calculate the change
Change = amount paid − total cost.
Method A: Subtract
$20.00 − $11.15 = $8.85
Method B: Count up (how cashiers do it)
To count up, start at the cost and add coins and bills until you reach the amount paid.
| From | Add | Reach |
|---|---|---|
| $11.15 | dime | $11.25 |
| $11.25 | 3 quarters | $12.00 |
| $12.00 | toonie and loonie | $15.00 |
| $15.00 | $5 bill | $20.00 |
Change: 10¢ + 75¢ + $3 + $5 = $8.85.
Counting up also tells you which coins to give.
Do I have enough?
Round prices up and add quickly. If the rounded total is less than what you have, you have enough.
Example: $3.89 + $4.29 + $1.75 ≈ $4 + $5 + $2 = $11. With $12, you’re fine.
Worked examples
Example 1: You buy juice for $1.85 and pay with a toonie. Change?
$2.00 − $1.85 = $0.15 (a dime and a nickel).
Example 2: Three snacks cost $2.25 each. Total?
3 × $2.25 = $6.75.
Example 3: A cash total is $7.42. What do you pay?
Rounds to $7.40.
Common mistakes
- Not lining up decimal points when adding prices.
- Subtracting the wrong way (cost − paid).
- Forgetting cash rounding in Canada.
Try it yourself
- Add $4.65 and $3.80.
- You pay $10 for an item costing $6.35. Find the change.
- A cash total is $15.98. What do you pay?
- Use counting up to find the change from $5 for a $3.70 item.
Answers: 1) $8.45 2) $3.65 3) $16.00 4) $1.30 (count up 3 dimes to $4.00, then a loonie to $5.00)
Quick recap
- Add prices for the total cost; line up decimals.
- Change = amount paid − total; count up to check.
- Cash totals in Canada are rounded to the nearest 5 cents.