Perimeter vs Area — Knowing the Difference (Grades 4–5)
Perimeter is the distance around a shape (add up all the side lengths); area is the space inside (square units). It's easy to mix them up — fencing a yard is perimeter; sodding it is area. For a rectangle, perimeter = 2 × (length + width) and area = length × width.
Understanding perimeter vs area
Perimeter is the distance around a shape (add up all the side lengths); area is the space inside (square units). It's easy to mix them up — fencing a yard is perimeter; sodding it is area. For a rectangle, perimeter = 2 × (length + width) and area = length × width.
Key Idea
Perimeter is the distance around a shape (add up all the side lengths); area is the space inside (square units). It's easy to mix them up — fencing a yard is perimeter; sodding it is area. For a rectangle, perimeter = 2 × (length + width) and area = length × width.
Seeing it in action
Worked example
A rectangle is 5 by 3. Find its perimeter and area.
Perimeter = 2 × (5 + 3) = 16 units. Area = 5 × 3 = 15 square units.
Perimeter goes around; area fills inside.
Try a few
Rectangle 4 by 6 — perimeter?
2 × 10.
Square side 5 — area?
Rectangle 2 by 8 — perimeter and area?
Perimeter Patrol
A calm tile-grid game for building and reading area and perimeter.
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