Examples for 8th grade - page 68

  1. Annulus
    medzikruzie Calculate the area of two circles annulus k1 (S, 3 cm) and k2 (S, 5 cm).
  2. Pigs
    prasce Pigs are feed by beet.Beet feed containing 12% dry solids, which is 0.72% of digestible crude protein. How much beet must beconsumed in one month (30 days), if the weight of digestible crude protein contained in a daily dose of beet was 0.912 kg?
  3. Algebrogram
    plus_2 Solve algebrogram: mama+anna=vari How many solutions are?
  4. Cuboid box
    box How many m2 paper is needed for the sticking cuboid box of dimensions 50 cm, 40 cm and 30 cm? To the folds add one-tenth the area.
  5. Testing
    test_3 Students of high school have 10 points for each good solved task. The wrong answer is deducted by 5 points. After solving 20 tasks, student Michael had 80 points. How many tasks did he solve correctly and how many wrong?
  6. Rectangle 3-4-5
    diagonal_rectangle_1 The sides of the rectangle are in a ratio of 3:4. The length of the rectangle diagonal is 20 cm. Calculate the content of the rectangle.
  7. 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.
  8. Copper wire
    cu_wire_1 What is the weight of 1000 m copper wire with a diameter of 5 mm when rezistivity p = 8.8 g / cm3?
  9. Locomotive
    locomotive_1 Locomotive pulled a train permanent load of 200 kN horizontally along the track of 5km. What work it done?
  10. 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).
  11. Water lake
    jezirko The length of the lake water is 8 meters width 7 meters and depth 120 centimeters. How many liters of water can fit into the water lake?
  12. Dealer
    canon Dealer sell digital camera for € 474. Thirty percent of the price was his profit. After some time, decreased interest in selling the camera and therefore reduce its sales price by 11 %. How many percent of the new price now is dealer's profit? Round the
  13. Pages of book
    books_2 Lenka calculated that if every day to read 16 pages of the book, read a book a day earlier than had read only 14 pages a day. How many pages has this book?
  14. Product - quadratic equation
    circles_3 Product of two numbers is 900. If we increase lowest number by 2 then product will increase by 150. Determine both numbers.
  15. 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?
  16. 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?
  17. Painting
    malovka 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.
  18. Isosceles trapezoid v3
    rovnobezky_uhly In an isosceles trapezoid ABCD is the size of the angle β = 81° Determine size of angles α, γ and δ.
  19. Hostel
    student Students are accommodated in 22 rooms. Rooms were 4 and 6 bed. How many rooms in which type occupied 106 children there?
  20. Task of the year
    years Determine the number of integers from 1 to 106 with ending four digits 2006.

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