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Class 7 Maths — Area of triangles and parallelograms

Find the area of a parallelogram, a triangle and a rhombus, and the perimeter of a straight-sided shape.

Name: ________________________

  1. 1.A parallelogram has a base of 8 cm and a height of 5 cm. What is its area, in square centimetres?

  2. 2.A triangle has an area of 24 square centimetres and a base of 8 cm. What is its height, in centimetres?

  3. 3.A square field has a side of 25 m. What is its perimeter, in metres?

  4. 4.Sort each rule by what it works out.

    Groups: Area · Perimeter

    • 1/2 × base × height
    • 4 × side
    • all the sides added together
    • 2 × (length + width)
    • base × height
    • length × width

  5. 5.A triangle and a parallelogram share the same base and the same height. The triangle's area is...

    • a) twice the parallelogram's area
    • b) half the parallelogram's area
    • c) impossible to compare
    • d) the same as the parallelogram's area

  6. 6.A parallelogram has an area of 60 square centimetres and a base of 10 cm. What is its height, in centimetres?

  7. 7.The height of a parallelogram is measured...

    • a) at right angles to the base
    • b) all the way round the outside
    • c) along the slanting side
    • d) from one corner to the opposite corner

  8. 8.A path runs all the way round a rectangular garden 20 m long and 15 m wide. How far is it once round the garden, in metres?

Answer key — Class 7 Maths — Area of triangles and parallelograms

  1. 1. 40
  2. 2. 6
  3. 3. 100
  4. 4. base × height → Area; 1/2 × base × height → Area; 2 × (length + width) → Perimeter; 4 × side → Perimeter; length × width → Area; all the sides added together → Perimeter
  5. 5. b) half the parallelogram's area
  6. 6. 6
  7. 7. a) at right angles to the base
  8. 8. 70