Perimeter (Year 4)
Calculate the perimeter of 2D shapes by adding side lengths.
The questions below are generated to match the National Curriculum for Year 4 and get harder as you progress from Rookie to Guru.
Worked examples
RookieRead and interpret directly.
How many centimetres are in 1 metre?
- 100
- 10
- 1,000
- 50
Answer: 100. 1 metre = 100 centimetres.
ProCompare and infer.
Which is LONGER: 1.5 m or 145 cm?
- 1.5 m
- 145 cm
- They are equal
- Cannot tell
Answer: 1.5 m. 1.5 m = 150 cm; 150 > 145.
GuruMulti-step reasoning.
Why does the formula A = L × W give cm² as the unit (not cm)?
- Because we multiply length × length — each in cm — and cm × cm = cm² (square centimetres).
- Because the answer is bigger than length.
- Because two-digit numbers always have squared units.
- Because the question said so.
Answer: Because we multiply length × length — each in cm — and cm × cm = cm² (square centimetres).. Multiplying cm × cm gives cm² — square centimetres — because we're measuring area.
Related skills
Frequently asked questions
- What is perimeter?
- Calculate the perimeter of 2D shapes by adding side lengths.
- How can my child practise perimeter at home?
- Work through the examples below, then start a free adaptive session. Northstar adjusts the difficulty automatically and tracks mastery over time.
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