Examples for 8th grade - page 66

  1. Chord distance
    tetiva The circle k (S, 6 cm), calculate the chord distance from the center circle S when the length of the chord is t = 10 cm.
  2. Pyramid 4sides
    pyramid_2 Calculate the volume and the surface of a regular quadrangular pyramid when the edge of the base is 4 cm long and the height of the pyramid is 7 cm.
  3. Double percent
    percents What is 70% of 70% of 10500?
  4. Rectangle
    rectangles_8 Perimeter of rectangle is 48 cm. Calculate its dimensions if they are in the ratio 5:3 (width:height)
  5. Diamond
    diagonals-rhombus Calculate the length of the two diagonals of the diamond if: a = 13 cm v = 12 cm
  6. Trapezoid v3
    licho_3 The isosceles trapezoid has the angle at a firsst base 40 degrees less than the angle at second base. How large angles has this trapezoid ?
  7. Sweets
    sladkosti 3 chocolate and 7 cakes cost 85, - CZK. 2 chocolates and 6 cakes cost 86, - CZK. How much is 5 chocolates and 9 cakes? I wonder how to get the result, but only by logic without the use of a system of equations
  8. Parcel
    2186094 parcel has a rectangular shape of a trapezoid with bases 12 m and 10 m and a height 8 m. On parcel was built object with a footprint an isosceles triangle shape with side 4 m and height three-quarters of a meter. What is the area of unbuild parcel?
  9. Painters
    natieraci Five painters painting the fence for eight days. How many days over will take work if paint the fence only four decorators?
  10. Cube
    krychlicka Calculate the surface of the cube ABCDA'B'C'D' if the area of rectangle ACC'A' = 344 mm2.
  11. Cenda and Pepa
    suchacky Cenda and Pepa went to the event. Cenda started alone. Canda started after him for 20 minutes. How long took Cenda to catch him? Cenda traveling at 15 km/h, and Pepa traveling at 25 km/h.
  12. Tiles
    100dlazdic How many tiles of 20 cm and 30 cm can build a square if we have a maximum 100 tiles?
  13. Binomials
    two_persons To binomial ? add a number to the resulting trinomial be square of binomial.
  14. Saving
    euro2 The boy has saved 50 coins € 5 and € 2. He saved € 190. How many were € 5 and how many € 2?
  15. The farmer field
    farma_pole The field has paralleogram shape with dimensions side a = 65 m and height 429 m. Two and two sides is at angle 65°. Calculate acreage of field in hectares.
  16. Sides od triangle
    podobnost Sides of the triangle ABC has length 4 cm, 5 cm and 7 cm. Construct triangle A'B'C' that are similar to triangle ABC which has a circumference of 12 cm.
  17. Playground
    plot_ihrisko.JPG Fencing square playground cost € 303; 1 meter cost € 15. What is the area of the playground?
  18. Aquarium volume
    akvarium_2 The aquarium has a cuboid shape and dimensions a = 0.3 m, b = 0.85 m, c =? , V = ?. What volume has a body, if after dipping into the aquarium water level rises by 28 mm?
  19. Inscribed circle
    inscribed_circle XYZ is right triangle with right angle at the vertex X that has inscribed circle with a radius 5 cm. Determine area of the triangle XYZ if XZ = 14 cm.
  20. Mortgage
    hypo_real_estate Family XY wants to take the bank mortgage (loan for an apartment/house) in the amount of € 100,000. Bank for processing the mortgage charges a fee of 0.79% of the amount borrowed. How many euros is this fee?

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