Perimeter of a parallelogram, step by step
A parallelogram has two pairs of equal sides, so its perimeter is twice one side plus twice the other.
The question
cm
Perimeter of a 15 by 8 parallelogram
sides:158158
sides:158158
sides:158158
15 + 8 + 15 + 8=46 cm
- Perimeter is the distance round the OUTSIDE — the length of the fence, not the size of the field. That is the whole difference between this and area, and it is where the usual wrong answer comes from.
- So there is nothing to work out — just walk round the edge and add: 15 + 8 + 15 + 8.
- 15 + 8 + 15 + 8 = 46 cm. Note the unit: cm, not square cm — a fence is a length, and a length never gets squared.
How it works.
- 01
Perimeter is the distance round the OUTSIDE — the length of the fence, not the size of the field. That is the whole difference between this and area, and it is where the usual wrong answer comes from.
- 02
So there is nothing to work out — just walk round the edge and add: 15 + 8 + 15 + 8.
- 03
15 + 8 + 15 + 8 = 46 cm. Note the unit: cm, not square cm — a fence is a length, and a length never gets squared.