Examples for 8th grade - page 69

  1. 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).
  2. 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?
  3. Locomotive
    locomotive_1 Locomotive pulled a train permanent load of 200 kN horizontally along the track of 5km. What work it done?
  4. 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.
  5. 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
  6. 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.
  7. 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?
  8. 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?
  9. 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.
  10. Gasoline
    fuel_3 For nearly full tank of 40 liters of gasoline chauffeur paid 54 euros. How many euros it will cost to go 250 km long if the car has an average fuel consumption 7 liters per 100 kilometers?
  11. Wood cuboid
    dub What is the weight of the wood cuboid 15 cm, 20 cm, 3 m if 1 m3 wood weighs 800 kg?
  12. Odd numbers
    friends4_2 The sum of four consecutive odd numbers is 1048. Find those numbers ...
  13. Hostel
    student Students are accommodated in 22 rooms. Rooms were 4 and 6 bed. How many rooms in which type occupied 106 children there?
  14. Digging
    Dighole A pit is dug in the shape of a cuboid with dimensions 10mX8mX3m. The earth taken out is spread evenly on a rectangular plot of land with dimensions 40m X 30m. What is the increase in the level of the plot ?
  15. Real estate
    house Residential house has three entrances numbered by odd numbers arithmetic progression. The sum of the two numbers on the corner entrances is 50. Calculate the highest of this three numbers.
  16. Enrollment
    enrollment The enrollment at a local college increased 4% over last year's enrollment of 8548. Find the increase in enrollment (x1) and the current enrollment (x2).
  17. Task of the year
    years Determine the number of integers from 1 to 106 with ending four digits 2006.
  18. Freezer
    mraznicka The freezer has the shape of a cuboid with internal dimensions of 12 cm, 10 cm, 30 cm. A layer of ice of 23 mm thick was formed on the inner walls (and on the opening) of the freezer. How many liters of water will drain if we dispose the freezer?
  19. Four swords
    fight Obelix has three helmets, four swords and five shields. How many swords must make at the blacksmith forge Metallurgix to be able to walk another 90 days in unique armor?
  20. Sphere vs cube
    koule_krychle_1 How many percent of the surface of a sphere of radius 12 cm is the surface of a cube inscribed in this sphere?

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