Beyond Rankers Academy
Building Minds, Not Just Rankers
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Beyond Rankers Academy
Building Minds, Not Just Rankers
Main site →
Perimeter measures the way round. Area measures the space inside. And a figure made of two shapes stuck together just needs its area worked out in two easy pieces.
Perimeter is the total distance all the way round a shape. For a REGULAR polygon (all sides equal), there is a shortcut.
Regular polygon shortcut
Perimeter = number of sides × length of one side
A regular pentagon with 6 cm sides: perimeter = 5 × 6 = 30 cm.
Area of a rectangle = length × breadth. Area of a square = side × side.
A figure made of two rectangles stuck together — or one with a corner cut off — is just an addition or subtraction of two simple areas.
12 IMO-style questions on perimeter, area and composite figures. 🍀