# Examples of area of plane shapes

Area is the quantity that expresses the extent of a two-dimensional shape. The area can be understood as the amount of paint necessary to cover the surface with a single coat. The area of a shape can be measured by comparing the shape to squares of a fixed size 1 m^2 or 1 cm^2 etc. Every unit of length has a corresponding unit of area. Areas can be measured in square metres (m^2), square centimetres (cm^2), square millimetres (mm^2), square kilometres (km^2), square feet (ft^2), square yards (yd^2), square miles (mi^2), and so forth.

#### Number of problems found: 757

• Perimeter of the circle Calculate the perimeter of the circle in dm, whose radius equals the side of the square containing 0.49 dm2?
• The resistance What is the resistance of an aluminum wire 0.2 km long and 10 mm in diameter?
• Equilateral triangle v3 Calculate the content of the colored gray part. Equilateral triangle has side length 8 cm. Arc centers are the vertices of a triangle.
• Three altitudes A triangle with altitudes 4; 5, and 6 cm is given. Calculate the lengths of all medians and all sides in a triangle.
• Annulus The radius of the larger circle is 8cm, the radius of smaller is 5cm. Calculate the contents of the annulus.
• Percentage of waste In a square plate with side 75 cm we cut 4 same circles. Calculate the percentage of waste.
• Pool tiles The pool is 25m long, 10m wide and 160cm deep. How many m2 of tiles will be needed on the walls and the pool? How many pieces of tile are needed when 1 tile has a square shape with a 20cm side? How much does it cost when 1m2 of tiles costs 258 Kc?
• Black building Keith built building with a rectangular shape 6.5 m × 3.9 m. Calculate how much percent exceeded the limit 25 m2 for small building. Building not built in accordance with the law is called "black building". Calculate the angle that the walls were clenchi
• Goat Meadow is a circle with radius r = 19 m. How long must a rope to tie a goat to the pin on the perimeter of the meadow to allow goat eat half of meadow?
• Cylinder container The cylindrical container with a diameter of 1.8 m contains 2,000 liters of water. How high does the water reach?
• Quarter of a circle Calculate the circumference of a quarter circle if its content is S = 314 cm2.
• Aquarium The box-shaped aquarium is 40 cm high; the bottom has dimensions of 70 cm and 50 cm. Simon wanted to create an exciting environment for the fish, so he fixed three pillars to the bottom. They all have the shape of a cuboid with a square base. The base edg
• The body The body on the figure consists of cubes with an edge length 10 cm. What surface has this body?
• Roller Roller has a diameter of 0.96 m and a width 169 cm. How many m2 of road level when he turns 42-times?
• Tetrahedral pyramid What is the surface of a regular tetrahedral (four-sided) pyramid if the base edge a=16 and height v=16?
• Pyramid height Find the volume of a regular triangular pyramid with edge length a = 12cm and pyramid height h = 20cm.
• Trapezium bases Find the trapezium height if a = 8 cm and c = 4 cm if its content 21 square centimeters.
• Diamond Determine the side of diamond if its content is S = 353 cm2 and one diagonal u2 = 45 cm. Calculate the content of a regular 15-sides polygon inscribed in a circle with radius r = 4. Express the result to two decimal places.
• Diver Please calculate using Pascal's law. The window of the diving helmet has a surface content of about 7dm2. Calculate what pressure force acts on the window at a depth of 20 meters below the water surface.

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