Examples for 8th grade - page 10

  1. Rhombus
    rhombus_1 Find the length of the other diagonal and area of rhombus. The perimeter of a rhombus is 40 cm and one of the diagonals is of length 10 cm.
  2. Pizza
    pizza_2 Pizza with a diameter 50 cm have weight 559 g. What diameter will have a pizza weighing 855 g if it is make from the same cloth (same thickness....) and same decorated?
  3. Acid
    acid_1 The barrel is 199 litres of 38% acid. How many percent acid occurs when 61 litres revoke and replace it with the same amount of water?
  4. Climb
    Mazda_RX7_1 On the road sign, which informs the climb is 8.7%. Car goes 5 km along this road. What is the height difference that car went?
  5. ISO triangle
    rr Calculate the area of an isosceles triangle KLM if the length of its sides are in the ratio k:l:m = 4:4:3 and has perimeter 377 mm.
  6. Tape
    mg Video is 153% more expensive than tape recorder. How many percent is tape recorder less expensive than video?
  7. Triangular prism
    TriangularPrism Plane passing through the edge AB and the center of segmet CC' of regular triangular prism ABCA'B'C', has angle with base 22 degrees, |AB| = 6 cm. Calculate the volume of the prism.
  8. Cone
    truncated_cone_1 Circular cone with height h = 29 dm and base radius r = 3 dm slice plane parallel to the base. Calculate distance of the cone vertex from this plane, if solids have the same volume.
  9. Tourists
    hiking From the cottage started first group of tourists at 10:00 AM at speed 4 km/h. The second started after them 47 minutes later at speed 6 km/h. How long and how many kilometers from the cottage will catch the first group?
  10. Garden
    garden_2 Father dig up the garden in 9 hours. Son in 13 hours. How many hours take dig up the garden together?
  11. Prism
    cuboid_2 Three cubes are glued into prism, sum of the lengths of all its edges is 115 cm. What is the length of one edge of the original cube?
  12. Shelf
    bookshelf.JPG How many ways are there to arrange 6 books on a shelf?
  13. Diagonals of the rhombus
    diagonals_rhombus Calculate height of rhombus whose diagonals are 12 cm and 19 cm.
  14. Bicycle wheel
    bicycle A bicycle wheel has a diameter of 60 cm. Approximately how many times does wheel rotate at 2.5 km long trip?
  15. Rhombus 2
    koso Calculate the area of rhombus which has a height v=48 mm and shorter diagonal u = 60 mm long.
  16. Tower
    cone_roof How many m2 of copper plate should be to replace roof of the tower conical shape with diameter 24 m and the angle at the vertex of the axial section is 144°?
  17. Profitable bank deposit 2012
    eurocoins Calculate the value of what money lose creditor with a deposit € 9500 for 4 years if the entire duration are interest 2.6% p.a. and tax on interest is 19% and annual inflation is 3.7% (Calculate what you will lose if you leave money lying idle at negative
  18. Cube
    kocka_rubik The cube weighs 11 kg. How weight is cube of the same material, if its dimensions are 3-times smaller?
  19. Equilateral triangle
    3angle_in_circle How long should be the minimum radius of the circular plate to be cut equilateral triangle with side 19 cm from it?
  20. Hexagon A
    hexagon Calculate area of regular hexagon inscribed in circle with radius r=9 cm.

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