Areas and perimeters
Types of exercises: area of rectangle, perimeter of a rectangle, side from the area, perimeter of a polygon, perimeter of a polygon - sides in different units, area of a square, perimeter of a shape on a grid.
Exercises are drawn at random from a large bank - every click gives a different set.
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Problem
A triangle has sides of 15 cm, 1.7 dm and 18 cm. How many centimetres is its perimeter?
Work out
The area of a rectangle: a = 3 m, b = 17 m
Problem
A rectangle has an area of 80 cm² and one side of 5 cm. How long is the other side?
Problem
A quadrilateral has sides of 11 m, 2 m, 6 m and 4 m. How many metres is its perimeter?
Problem
The drawing shows a polygon whose sides run along the grid lines. Each grid square has sides of 1 cm. How many centimetres is the perimeter of this polygon?
Problem
The area of a square is 121 cm². How many centimetres long is its side?
Work out
The perimeter of a rectangle: a = 17 m, b = 15 m
Problem
A quadrilateral has sides of 190 mm, 2 dm, 60 mm and 1.7 dm. How many centimetres is its perimeter?
Work out
The area of a rectangle: a = 24 cm, b = 16 cm
Problem
A rectangle has an area of 156 m² and one side of 12 m. How long is the other side?
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