Surface area + percentages - math problems

Number of examples found: 38

  • Cube wall
    kocka Surface of first cube wall his 225 mm2. Second cube area is 60% of the surface of the first cube. Determine the length of the edge of the second cube (x).
  • Surface area 2
    cubes Calculate how many % reduce the surface area of the cube is we reduced length of each edge by 10%.
  • Cube surface area
    cubes2_2 The surface of the cube was originally 216 centimeters square. The surface of the cube has shrunk from 216 to 54 centimeters sq. Calculate how much percent the edge of the cube has decreased.
  • Seat
    cubes3 How much m² of fabric do we need to sew a 50cm-shaped cube-shaped seat if 10% of the material we add to the folds?
  • Content area and percents
    squares_8 Determine what percentage is smaller cube surface, when the surface area of the wall decreases by 25%.
  • Sphere vs cube
    koule_krychle How many % of the surface of a sphere of radius 12 cm is the surface of a cube inscribed in this sphere?
  • Sphere radius
    SpheresDiff The radius of the sphere we reduce by 1/3 of the original radius. How much percent does the volume and surface of the sphere change?
  • Earth's surface
    earth_globe The greater part of the earth's surface (r = 6371 km) is covered by oceans; their area is approximately 71% of the Earth's surface. What is the approximate area of the land?
  • The surface area
    cuboid_1 How much percent will the surface area of a 4x5x8 cm block increase if the length of the shortest edge is increased by 2 cm?
  • Gutter pipe
    odkvap_zlab How many m² of sheet metal is required to produce a 12 m long and 18 cm wide gutter, if 7% bend is required?
  • Metal box
    box1 How much metal we need for the production of box with dimensions 5 dm, 30 cm and a height of 1 m? Add 12% of the waste and folds.
  • Alaska vs Montana
    montana Alaska is the largest state in the United States and has a surface area of approximately 588,000 square miles. Montana has a surface area that is approximately 25% of the surface area of Alaska. What is the approximate surface area of Montana?
  • Cube zoom
    krychle_1 How many percents do we increase the volume and surface of the cube if we magnify its edge by 38 %?
  • Tropical, mild and arctic
    tropic How many percents of the Earth's surface lies in the tropical, mild and arctic range? The border between the ranges is the parallel 23°27 'and 66°33'.
  • Water tank
    nadrz_13 A 288 hectoliter of water was poured into the tank with dimensions 12 m and 6 m bottom and 2 m depth. What part of the volume of the tank water occupied? Calculate the surface of tank wetted with water.
  • Cone roof
    kuzel2 How many m2 of roofing is needed to cover a cone-shaped roof with a diameter of 10 m and a height of 4 m? Add an extra 4% to the overlays.
  • Tent
    polygonal_pyramid Pyramid-shaped tent has a base square with a side length of 2 m and a height 1.7 m. How many meters of canvas is nneded to make it if for a waste should be added 10%?
  • The ball
    sphere4 The ball has a radius of 2m. What percentage of the surface and volume is another sphere whose radius is 20% larger?
  • Storm and roof
    cone_church The roof on the building is a cone with a height of 3 meters and a radius equal to half the height of the roof. How many m2 of roof need to be repaired if 20% were damaged in a storm?
  • Gutter
    okap How much metal is needed for production 60 pieces of gutter pipes with the diameter 17 cm and length of 6 m? The plate bends add 6% of the material.

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