Area - 8th grade (13y) - math problems

Number of problems found: 646

  • Mysterious area
    lichobeznik The trapezoid ABCD is given. Calculate its area if the area of the DBC triangle is 27 cm2.
  • In the
    land_6 In the national park, the ratio of the wooded area to grassland is 4: 1. The total area is 385km2. What area is wooded?
  • Screens
    tv2_3 The area of a 25 inch TV screen is 300 inch² the area of a 40 inch TV screen is 768 inch². The area of the smaller screen is what percent of the area of the larger screen?
  • 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?
  • Cllub flag
    flg The children had the club flag sewn on. The red color covered 2/20 of the total area of the flag, the blue area a fifth, the yellow 19% of the total area. What% is the green area occupied?
  • Area to perimeter
    circle11_3 Calculate circle circumference if its area is 254.34cm2
  • Content area and percents
    squares_8 Determine what percentage is smaller cube surface, when the surface area of the wall decreases by 25%.
  • Conical area
    cones_2 A right angled triangle has sides a=12 and b=19 in right angle. The hypotenuse is c. If the triangle rotates on the c side as axis, find the volume and surface area of conical area created by this rotation.
  • MO8-Z8-I-5 2017
    mo8 Identical rectangles ABCD and EFGH are positioned such that their sides are parallel to the same. The points I, J, K, L, M and N are the intersections of the extended sides, as shown. The area of the BNHM rectangle is 12 cm2, the rectangle MBCK area is 63
  • Diamond area from diagonals
    kosostvorec In the diamond ABCD is AB = 4 dm and the length of the diagonal is 6.4 dm long. What is the area of the diamond?
  • Surface area 6
    prism3s Find the surface area of a prism whose bases are right triangles with sides of length 3, 4, and 5 inches and a height of 8 inches. Include a sketch
  • Maximum area of rhombus
    rhombus Calculate the interior angles at which equilateral rhombus has a maximum area.
  • Divide
    rectangles_12 Divide area of rectangles with dimensions 32m and 10m by the ratio 7: 9. What area corresponds to a smaller section?
  • Diagonal to area
    rectangle_5 Calculate the area of a rectangle in which the length of the diagonal is 10 cm.
  • Inscribed rectangle
    circle_desc_rectangular The circle area is 216. Determine the area of inscribed rectangle with one side 5 long.
  • Surface area
    cone_slice The volume of a cone is 1000 cm3 and the content area of the axis cut is 100 cm2. Calculate the surface area of the cone.
  • Cylinder surface area
    cylinder_2 Volume of a cylinder whose height is equal to the radius of the base is 678.5 dm3. Calculate its surface area.
  • Circles
    SquareCircleSquare Area of circle inscribed in a square is 14. What is the area of a circle circumscribed around a square?
  • Map
    mapa_bce Forest has an area of ​​36 ha. How much area is occupied by forest on the map at scale 1:500?
  • Rectangle area
    rectangles_5 The length of a rectangle of x units is increased by 10% and its width of y units is increased by 15%. What is the ratio of the area of the old rectangle to the area if the new rectangle?

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