17.2 Plans and elevations — Practise
Work independently, then check your answers and reasoning.
- A cuboid is 8 cm wide, 5 cm deep and 3 cm high. Give its plan dimensions.
- For the cuboid above, give the front elevation dimensions.
- For the cuboid above, give the side elevation dimensions.
- A stack has three unit cubes in a row on the bottom and one cube on top of the middle cube. How many squares appear in its plan?
- For that stack, the front elevation has what maximum height in cube units?
- A plan is 6 cm by 4 cm. Can it alone determine the solid height? Explain.
- A cuboid has dimensions 9 cm, 4 cm and 2 cm. Which two dimensions appear in its front elevation if 9 cm is the width?
- A triangular prism has a triangular cross-section 3 cm high. What height appears in its front elevation if viewed square-on to that end?
Answers and concise solutions
1. A cuboid is 8 cm wide, 5 cm deep and 3 cm high. Give its plan dimensions.
Answer: 8 cm by 5 cm
2. For the cuboid above, give the front elevation dimensions.
Answer: 8 cm by 3 cm
3. For the cuboid above, give the side elevation dimensions.
Answer: 5 cm by 3 cm
4. A stack has three unit cubes in a row on the bottom and one cube on top of the middle cube. How many squares appear in its plan?
Answer: 3 squares
5. For that stack, the front elevation has what maximum height in cube units?
Answer: 2 units
6. A plan is 6 cm by 4 cm. Can it alone determine the solid height? Explain.
Answer: No; a plan shows width and depth, not height.
7. A cuboid has dimensions 9 cm, 4 cm and 2 cm. Which two dimensions appear in its front elevation if 9 cm is the width?
Answer: 9 cm by 2 cm
8. A triangular prism has a triangular cross-section 3 cm high. What height appears in its front elevation if viewed square-on to that end?
Answer: 3 cm