The idea, step by step
Compare like with like
If two ribbons are measured with the same tiles, the one with more tiles is longer. Start at one end and measure carefully.
The same idea works for mass and capacity. Nine equal counters balance more mass than six. Seven full cups hold more than four of the same cup.
Find how much more
Compare 7 units with 4 units by counting on from 4 to 7, or by subtracting: 7 - 4 = 3. Row A is 3 blocks longer.
Do not compare a count of large cups with a count of small cups until you know how they are related. The unit matters as much as the number.
A common trap
The larger number always means the larger object.
Instead: First check that the units match. Small-unit counts cannot be directly compared with large-unit counts.
See the thinking
Longer by how much?
Stick A is 9 blocks long. Stick B is 6 of the same blocks long. How much longer is A?
- The unit is the same.
- 9 - 6 = 3.
An unfair comparison
A pot holds 5 small cups. A jug holds 4 large cups. Does the pot definitely hold more?
- The cups have different sizes.
- Five small cups might hold less than four large cups.
- Measure both with the same cup.
Check your understanding
A tub holds 8 cups. A bowl holds 5 of the same cups. How much more does the tub hold?
Show answer
3 cups more.
8 - 5 = 3.
Your turn
6 questions · Work at your own pace.
Read the questions online
- Ribbon A is 8 tiles long. Ribbon B is 5 of the same tiles long. Which is longer?
- A jar holds 9 scoops. A bowl holds 6 of the same scoops. How many more scoops does the jar hold?
- Toy A balances with 4 equal counters. Toy B balances with 7 of the same counters. Which has less mass?
- Order these lengths from shortest to longest: 6 blocks, 3 blocks, 8 blocks. All blocks match.
- A board is 6 hand spans long. A shelf is 5 shoe lengths long. Can you decide which is longer from these counts?
- How many blocks longer is row A than row B?
Read the worked solutions
- Ribbon A is 8 tiles long. Ribbon B is 5 of the same tiles long. Which is longer?
8 is greater than 5.
Ribbon A. - A jar holds 9 scoops. A bowl holds 6 of the same scoops. How many more scoops does the jar hold?
9 - 6 = 3.
3 scoops. - Toy A balances with 4 equal counters. Toy B balances with 7 of the same counters. Which has less mass?
4 equal counters have less mass than 7.
Toy A. - Order these lengths from shortest to longest: 6 blocks, 3 blocks, 8 blocks. All blocks match.
3 < 6 < 8.
3 blocks, 6 blocks, 8 blocks. - A board is 6 hand spans long. A shelf is 5 shoe lengths long. Can you decide which is longer from these counts?
Hand spans and shoe lengths are different units.
No. - How many blocks longer is row A than row B?
A has 6 and B has 4.
6 - 4 = 2.
2 blocks longer.
Curriculum reference & lesson scope
Australian Curriculum v9 / SA Curriculum 2026
Length, mass and capacity; uniform informal units; smaller units for accuracy; comparison.
Official curriculum source ↗