Examples of area of plane shapes

Number of problems found: 668

  • Circle arc
    pizza Circle segment has a circumference of 135.26 dm and 2096.58 dm2 area. Calculate the radius of the circle and size of central angle.
  • Similarity n-gon
    podobnost 9-gones ABCDEFGHI and A'B'C'D'E'F'G'H'I' are similar. The area of 9-gon ABCDEFGHI is S1=190 dm2 and the diagonal length GD is 32 dm. Calculate area of the 9-gon A'B'C'D'E'F'G'H'I' if G'D' = 13 dm.
  • Black building
    talapka_cierna_stavba 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
  • Widescreen monitor
    lcd Computer business 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 same diagonal more advantageous than
  • Triangle
    trangle_nice Calculate heights of the triangle ABC if sides of the triangle are a=75, b=84 and c=33.
  • Concrete pipe
    concrete_pipe Concrete pipe is cylindrical with an inner diameter 110 cm and outer 120 cm. Calculate the surface of the concrete pipe, if it is 9 m long.
  • Rectangle - sides ratio
    rectangle_2 Calculate area of rectangle whose sides are in ratio 3:13 and perimeter is 673.
  • Area of trapezoid
    trapezoid The trapezoid bases are and 7 dm and 11 cm. His height is 4 cm. Calculate the area of trapezoid.
  • Glass mosaic
    6gon How many dm2 glass is nessesary to produc 97 slides of a regular 6-gon, whose side has length 21 cm? Assume that cutting glass waste is 10%.
  • Rectangles
    strihanie Calculate how many squares/rectangles of size 4×3 cm can be cut from a sheet of paper of 36 cm × 32 cm?
  • Isosceles right triangle
    3triangles Calculate the area of an isosceles right triangle whose perimeter is 377 cm.
  • Window
    buranie_otvoru Peter demolish box hole in the wall for window frame 147×51 cm. When they came masters fitted frame and window will be found that glass is 13.3 cm from the hole in each direction. Calculate how much percent less light enters the window than hole?
  • Garden
    garden Trapezoid garden has parallel sides 19 m and 24 m. Its area is 193.5 square meters. What is the width of the garden?
  • Rhombus HP
    rhombus3_1 Calculate area of the rhombus with height 24 dm and perimeter 12 dm.
  • Shape
    some_airplane Plane shape has a maximum area 677 mm2. Calculate its perimeter if perimeter is the smallest possible.
  • Present
    prezent Gift box has rectangular shape with dimensions of 8×8×3 cm. Miloslav wants to cover with square paper with sides of 18 cm. How much paper left him?
  • Rhombus problem
    privesok-kosostvorec Perimeter of the rhombus is 204 dm and it area is 2244 dm2. Calculate the height of the rhombus.
  • Circle in rhombus
    circle_rhombus In the rhombus is inscribed circle. Contact points of touch divide the sides to parts of length 19 cm and 6 cm. Calculate the circle area.
  • Maximum area of rhombus
    rhombus Calculate the interior angles at which equilateral rhombus has a maximum area.
  • Jewel
    rhombus3 Rhombus-shaped jewel have area of 93 mm2 and the edge in long 13.2 mm. Calculate the size of rhombus acute angle.

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