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P1 Maths: 2D Shapes (10 Challenge Items)
P1 Maths: 2D Shapes (10 Challenge Items)
Ten challenge items: telling a rhombus from a square, perimeters after joining, how cutting a corner changes the side count, equal perimeters with different areas, counting combined figures, and separating perimeter from area.
Focus Sketch the shape or list its edges before calculating, and always give the unit.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 |
| Suggested time | 25 |
| Difficulty mix | Foundation 4 · Intermediate 3 · Challenge 2 · Error redo 1 |
| Chapter | Chapter: P1 Maths: 2D Shapes |
| Level | P1 Maths |
02 Questions (10 items)
- FoundationA shape has four equal sides but no right angles. What is it?
- FoundationTwo squares with 6 cm sides are placed side by side. What is the perimeter of the rectangle formed?
- Foundation24 matches of 1 cm each are used to make a square. What is the side length?
- FoundationA 10 cm by 6 cm rectangle has a 2 cm square cut from one corner. How many sides does the remaining shape have?
- IntermediateA square has perimeter 20 cm. A 6 cm by 4 cm rectangle also has perimeter 20 cm. What is the square side length and the difference in area?
- IntermediateA pentagon has one corner cut off. How many sides does the new shape have?
- IntermediateFour squares with 3 cm sides form a large square. What are its side length and perimeter?
- ChallengeFrom triangles to quadrilaterals to pentagons and on to decagons, what is the pattern and how many sides does a decagon have?
- ChallengeA large triangle is split by one line from the top corner to the base. How many triangles are in the figure?
- Error redoA student says a longer perimeter always means a bigger area. Use 9 cm by 1 cm and 4 cm by 6 cm rectangles to respond.
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | A rhombus. | A square needs equal sides and right angles; without right angles it is a rhombus. |
| 2 | The rectangle is 12 cm by 6 cm, so the perimeter is (12 + 6) × 2 = 36 cm. | The two touching sides are hidden, so the answer is not 48 cm. |
| 3 | 24 ÷ 4 = 6 cm. | The number of matches equals the perimeter in centimetres. |
| 4 | 4 + 1 = 5 sides, so the remaining shape is a pentagon. | Cutting off a corner removes one corner but adds two edges, a net gain of one. |
| 5 | Side 20 ÷ 4 = 5 cm, area 25 cm²; the rectangle is 24 cm², a difference of 1 cm². | Shapes with the same perimeter can have different areas. |
| 6 | 5 − 1 + 2 = 6, so it becomes a hexagon. | Cutting a corner removes one vertex and creates two new ones. |
| 7 | Side 3 × 2 = 6 cm, perimeter 6 × 4 = 24 cm. | Four small squares form a 2 by 2 block, so the side doubles. |
| 8 | Each shape has one side more than the last, and a decagon has 10 sides. | The number in the name is the side count, so a decagon has 10. |
| 9 | Two small triangles plus the large one, so 3 in total. | Combined figures count too, not only the smallest pieces. |
| 10 | Both have perimeter 20 cm but areas of 9 cm² and 24 cm², so equal perimeter does not mean equal area. | Area and perimeter are separate measures and must be calculated separately. |
04 What to do after marking
- After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
- Repeat the same item two days later; move to the next paper only when both attempts are correct.
- Parents only need the answer and note columns; there is no need to explain every item.
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Questions and answers are written originally by the TutorZone team and are not taken from any school, publisher or examination authority paper. Every value is checked by computer.