# 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: 745

• Pipe cross section The pipe has an outside diameter 1100 mm and the pipe wall is 100 mm thick. Calculate the cross section of this pipe.
• Widescreen monitor Computer businesses hit by a wave of widescreen monitors and televisions. Calculate the area of ​​the LCD monitor with a diagonal size 20 inches at ratio 4:3 and then 16:9 aspect ratio. Is buying widescreen monitors with the same diagonal more advantageou
• Prism Right-angled prism, whose base is a right triangle with leg a = 3 cm and hypotenuse c = 13 cm, has the same volume as a cube with an edge length of 3 dm. a) Find the height of the prism b) Calculate the surface of the prism c) What percentage of the cube'
• Cutting square From a square with a side of 30 cm, we cut the circle with the highest possible diameter. How many percents of the square content is this circle?
• Tetrahedral pyramid Calculate the surface S and the volume V of a regular tetrahedral pyramid with the base side a = 5 m and a body height of 14 m.
• Shell of cylinder Calculate the content of shell the 1.6 m height cylinder with a base radius of 0.4 m.
• Rectangles How many different rectangles can be made from 60 square tiles of 1 m square? Find the dimensions of these rectangles.
• Chemical parison The blown parison (with shape of a sphere) have a volume 1.5 liters. What is its surface?
• Tiler On what surface m2 tiler must lay 30 square tiles, each of which has a side 25 cm?
• MO - triangles On the AB and AC sides of the triangle ABC lies successive points E and F, on segment EF lie point D. The EF and BC lines are parallel and is true this ratio FD:DE = AE:EB = 2:1. The area of ABC triangle is 27 hectares and line segments EF, AD, and DB seg
• The aquarium The aquarium has a capacity of 18 liters. What is its height when the square bottom is 8 2/3 cm long?
• Parcel Both dimensions of the rectangular parcel were increased by 26%. By how many % has increased its acreage?
• Two rectangles I cut out two rectangles with 54 cm², 90 cm². Their sides are expressed in whole centimeters. If I put these rectangles together I get a rectangle with an area of 144 cm2. What dimensions can this large rectangle have? Write all options. Explain your calc
• Perimeter of the circle Calculate the perimeter of the circle in dm, whose radius equals the side of the square containing 0.49 dm2?
• 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

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