# Surface area + percentages - math problems

#### Number of problems found: 41 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?
• Earth's surface 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?
• Content area and percents Determine what percentage is smaller cube surface, when the surface area of the wall decreases by 25%.
• Surface area 2 Calculate how many % reduce the surface area of the cube is we reduced length of each edge by 10%.
• The surface area 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?
• Cube surface area 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.
• Cube wall 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).
• Sphere vs cube How many % of the surface of a sphere of radius 12 cm is the surface of a cube inscribed in this sphere?
• 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' 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?
• Pyramid - angle Calculate the regular quadrangular pyramid's surface whose base edge measured 6 cm, and the deviation from the plane of the base's sidewall plane is 50 degrees.
• Cube zoom How many percents do we increase the volume and surface of the cube if we magnify its edge by 38 %?
• The ball The ball has a radius of 2m. What percentage of the surface and volume is another sphere whose radius is 20% larger?
• Tropical, mild and arctic 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'.
• Tropics and polar zones What percentage of the Earth’s surface lies in the tropical, temperate and polar zone? Individual zones are bordered by tropics 23°27' and polar circles 66°33'
• Water tank 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.
• Painting The room is long 50 meters and wide 60dm and 300 cm high. Calculate how much it will cost painting if area of windows and doors is 15% of the total area. One square meter cost 50cents.
• Church roof The roof of the church tower has the shape of a regular tetrahedral pyramid with base edge length 5.4 meters and a height 5 m. It was found that needs to be corrected 27% covering of the roof area. What amount of material will be required?
• The room The room has a cuboid shape with dimensions: length 50m and width 60dm and height 300cm. Calculate how much this room will cost paint (floor is not painted) if the window and door area is 15% of the total area and 1m2 cost 15 euro.
• Triangular prism The base of the perpendicular triangular prism is a rectangular triangle with a hypotenuse of 10 cm and one leg of 8 cm. The prism height is 75% of the perimeter of the base. Calculate the volume and surface of the prism.

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