The idea, step by step
Dollars contain cents
One dollar has the same value as 100 cents. Two dollars are 200 cents. To compare a mixture of dollars and cents, you can name all its value in cents.
Current Australian coins have values 5, 10, 20 and 50 cents, and 1 and 2 dollars. The number of coins does not tell their total value: read each coin's value.
| Money amount | Total cents | Price in dollars |
|---|---|---|
| 1 dollar 20 cents | 120 | 1.20 |
| 2 dollars 5 cents | 205 | 2.05 |
| 3 dollars 50 cents | 350 | 3.50 |
Read both cents places
A price written as 2.05 means 2 dollars and 5 cents. The zero holds the tens-of-cents place. A price of 2.50 means 2 dollars and 50 cents.
Australian notes have values 5, 10, 20, 50 and 100 dollars. For this practice, the money amounts are exact; no cash rounding is needed.
A common trap
Read 3.05 dollars as 3 dollars 50 cents.
Instead: The digits after the point name cents in two places. 05 is 5 cents; 50 is 50 cents.
See the thinking
Change cents into dollars and cents
Write 245 cents in dollars and cents.
- Take 200 cents as 2 dollars.
- There are 45 cents left: .
Keep the zero
Write 3 dollars 5 cents as total cents and as a price in dollars.
- 3 dollars are 300 cents.
- Add 5 cents: .
- Write the cents with two places, 05.
Check your understanding
How many cents are in 4 dollars 20 cents?
Show answer
420 cents.
4 dollars are 400 cents; .
Your turn
6 questions · Work at your own pace.
Read the questions online
- How many cents equal 1 dollar?
- Write 2 dollars 35 cents as total cents.
- Write 370 cents in dollars and cents.
- Read the price 5.05 dollars in words.
- Which is more: 2.50 dollars or 2.05 dollars? Explain.
- Name the Australian coin values below 1 dollar.
Read the worked solutions
- How many cents equal 1 dollar?
Use the dollar–cent relationship.
100 cents. - Write 2 dollars 35 cents as total cents.
.
235 cents. - Write 370 cents in dollars and cents.
300 cents are 3 dollars; 70 cents remain.
3 dollars 70 cents. - Read the price 5.05 dollars in words.
The two cents places show 05, or 5 cents.
5 dollars 5 cents. - Which is more: 2.50 dollars or 2.05 dollars? Explain.
Both have 2 dollars. 50 cents is more than 5 cents.
2.50 dollars is more. - Name the Australian coin values below 1 dollar.
The 1-dollar and 2-dollar coins are not below 1 dollar.
5 cents, 10 cents, 20 cents and 50 cents.
Curriculum reference & lesson scope
Australian Curriculum v9 and SA Curriculum Mathematics
Dollars/cents; equivalent amounts; modelling purchases; needs/wants; class enterprise and others' wellbeing.
Official curriculum source ↗