Examples for 8th grade - page 27

  1. Metal alloy
    ocel What is the ratio of metals in the alloy that is in the 50 tonnes of steel to 30 kg nickel?
  2. Journey
    Mt-Everest The road from A to B measures 11.5 km. Firstly up the hill, then by level plane and then downhill. Tourist goes uphill at 3 km/h, on the plane 4 km/h and downhill 5 km/h. From point A to B went 2h 54 min back 3h 6 min. How long is the segment of level pla
  3. Roller
    cestnyvalec Roller has a diameter of 0.97 m and a width 169 cm. How many m2 of road level when he turns 68-times?
  4. Tablecloth
    decka I embroider tablecloth in 20 days but if I embroider 3/4 hours a day I have embroider it for 15 days. How long do I embroider a day?
  5. Circumscription
    circles43 Calculate radius of the Circumscribed circle in the rectangle with sides 17 and 16. It can be rectangle inscribed by circle?
  6. Bomber
    b52 Bomber flies 5 km at 1400 km/h. At what horizontal distance from the target, must pilot drop the bomb to hit the target? Don't care about air resistance and consider the gravitational acceleration g=9.81 m/s2.
  7. Equilateral cylinder
    3d Equilateral cylinder (height = base diameter; h = 2r) has a volume of V = 221 cm3 . Calculate the surface area of the cylinder.
  8. Angles ratio
    3angle_1 In a triangle ABC true relationship c is less than b and b is less than a. Internal angles of the triangle are in the ratio 5:4:9. The size of the internal angle beta is:
  9. Height 2
    1unilateral_triangle Calculate the height of the equilateral triangle with side 43.
  10. Aircraft
    aircraft_soviet The aircraft has in a fuel tank 100 hl of aviation fuel and flight consumes 4.3 liters of fuel. Identify the function, which expresses the dependence of the volume of fuel in tank on the track distance plane flew by. How many hectolites of fuel is still i
  11. Carpenter
    tesari From wooden block carpenter cut off a small cuboid block with half the edge length. How many percent of wood he cut off?
  12. Unions
    odbory_prdel Calculate how much money per year would go to the treasury of unions if 447 thousand employee join unions with an average net salary of 539 euros and if memberhip in union cost 1% of the net monthly salary.
  13. Hexagonal prism
    hexa_prism The base of the prism is a regular hexagon consisting of six triangles with side a = 12 cm and height va = 10.4 cm. The prism height is 5 cm. Calculate the volume and surface of the prism!
  14. Gauss
    kfgauss Help little C.F. Gauss sum all the integers from 1 to 340.
  15. Divisors
    one Find all divisors of number 418. How many are them?
  16. Sawdust
    drevo_kmen_rez How many cubic centimeters of wood sawdust is created by cut the tree trunk with a diameter of 38 cm and when the gap width is 6 mm?
  17. Basements
    Spider-and-Fly In the first basement is more flies than the spiders, the second vice versa. Each basement had spiders and flies together 100 feet. Determine how many could be flies and spiders in the first and second basement. PS. We only need, when you write how many.
  18. Bridge
    bridge_circle The bridge arc has a span 41 m and height 3 m. Calculate the radius of the circle arc of this bridge.
  19. Paper box
    cuboid_5 Calculate the consumption of paper on the box-shaped quadrangular prism with rhombic footstall, base edge a=6 cm and the adjacent base edges forms an angle alpha = 60 °. Box height is 10 cm. How many m2 of the paper consumed 100 such boxes?
  20. Vacation
    motion Parents piggybacking children on vacation to its grandmother and grandfather at a city distant 150 kilometers. They agreed to meet halfway. Parents will be travel at 90 km/h, grandmother and grandfather at 60 km/h. Parents depart at 12:00 hours. When grand

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