Examples for 8th grade - page 65

  1. Suzan
    eliska My daughter reaches X years in X squared, said Suzan father in 2013 during the celebration of her birthday. When will given fact become reality and how many years at that time will have Suzan?
  2. Annulus
    medzikruzie Calculate the area of two circles annulus k1 (S, 3 cm) and k2 (S, 5 cm).
  3. Three friends
    oriental The three friends spent 600 KC in a teahouse. Thomas paid twice as much as Paul. Paul a half less than Zdeněk. How many each paid?
  4. Math heart
    srdce_1 Stylized heart shape created from a square with side 5 cm and two semicircles over his sides. Calculate the content area and its circumference.
  5. Saving
    euro2 The boy has saved 50 coins € 5 and € 2. He saved € 190. How many were € 5 and how many € 2?
  6. Football league
    football_1 In the 4th football league plays each of the 16 participants with each opponent twice. For every victory gets 3 points, 1 point for a draw, a defeat none. After the competition was team with 56 points and 8 defeats at 6th place. How many times have won?
  7. Sugar cubes
    cukr_5 The glass has 600 ml of tea, which represents 80% of the volume of the glass. If you put twenty regular sugar cubes of 2 cm in the tea, how many ml of tea are poured?
  8. Truncated cone
    komoly_kuzel A truncated cone has a base radius 40 cm and 10 cm and a height of 25 cm. Calculate its surface area and volume.
  9. Cone area and side
    cone_2 Calculate the surface area and volume of a rotating cone with a height of 1.25 dm and 17,8dm side.
  10. Jane
    gift Jane buy gift together for 464 Sk. For tie paid 4.5 times less than in the shirt, but 56 Sk more than for socks. How much she paid for each item in gift?
  11. Trapezium
    lichobeznik_3 The length of the base and the height size of the base of the trapezium is at ratio 5:3:2, the content area of the trapezium is 128 cm2. Calculate the length of the base and the height of the trapezoid.
  12. Grass garden
    koseni Mr. Grass would itself be mowed garden for 5 hours. His son Michael could do it for 7 hours. They agreed that they wake up at 5 am and begins to mow together. Ms. Grass needs drive into town at 8.30. Michael says that at that time they're done with work..
  13. 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?
  14. Rhombus and diagonals
    kosostvorec_2 The a rhombus area is 150 cm2 and the ratio of the diagonals is 3:4. Calculate the length of its height.
  15. Average mark
    flag_english Calculate average mark in English, if a student got a couple of 3's, 20% less 2 than 3, and 50% more 1's than the 2's.
  16. Tonic
    krem One package tonic consume Mom 12 weeks and daughter for 14 weeks. 4 weeks they use the same cream together and then only daughter. How many weeks endured tonic to daughter then?
  17. Right triangles
    PT How many right triangles we can construct from line segments 3,4,5,6,8,10,12,13,15,17 cm long? (Do not forget to the triangle inequality).
  18. Cube
    krychlicka Calculate the surface of the cube ABCDA'B'C'D' if the area of rectangle ACC'A' = 344 mm2.
  19. Isosceles trapezoid v3
    rovnobezky_uhly In an isosceles trapezoid ABCD is the size of the angle β = 71° Determine size of angles α, γ and δ.
  20. Painter
    painting_1 How many euros we will pay for repainting the room shaped cuboid with a length of 4.5 meters, width of 2.5 meters and a height of 3 meters, if for 1 m2 with paint we pay € 1.5?

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