Examples for 8th grade - page 22

  1. Column
    pole_phone Perpendicular pole high 6 m tall broke and its toe fell 2.8 m from the bottom of the pole. At what height above the ground pole broke?
  2. Prism
    cuboid_2 Three cubes are glued into prism, sum of the lengths of all its edges is 259 cm. What is the length of one edge of the original cube?
  3. The creek
    potok Workers cleaned the creek within 3 days. The first day cleanse one-fifth the length of the creek, the next day 40% of the length of the stream and the third day 8 km length of the creek. How long is a creek?
  4. Barrel 3
    sud-s-vodou Barrel with water has a weight 118 kg. When we get off 75% of water it has a weight 35 kg. How many kg has empty barrel?
  5. Rhombus
    pqrs PQRS is a rhombus. Given that PQ=4 cm & height of rhombus is given 1.8 cm. Calculate its area.
  6. Percentage reduction
    sales_percentages Reducing the unknown number by 36% get number 937.3 Determine unknown number.
  7. Midpoint of segment
    midpoint-segment Point A has coordinates [15; 1] and the midpoint of the segment AB is the point [-20; 13]. What are the coordinates of point B?
  8. Machines
    machinery In the workshop are three machines. The first is treated 350 parts for 4.3 hours, the second is treated 490 parts for 4.6 hours and the third is treated 360 parts for 3.7 hours. How long will take to make 3080 parts if worked all three machines at the.
  9. Pharmacy
    lekarna At the pharmacy are in one container 20% solution in the second 50% solution of disinfectant. They need to prepare 24 L of 36-percent solution. What amount of solution from each container is needed to mix?
  10. Distance
    distance Calculate distance between two points Z[7; -9] and U[-10; -8].
  11. Skiing meeting
    compass4 On the skiing meeting came four friends from 4 world directions and led the next interview. Charles: "I did not come from the north or from the south." Mojmir "But I came from the south." Joseph: "I came from the north." Zdeno: "I come from the south." W
  12. Cuboid
    kvadr Find the cuboid that has the same surface area as the volume.
  13. Book
    books_1 Alena read a book at speed 15 pages per day. If she read twice as fast she should read a book four days earlier. How many pages have a book?
  14. Circles
    two_circles The areas of the two circles are in the ratio 1:15. The larger circle has diameter 25. Calculate the radius of the smaller circle.
  15. Balance
    balance_weight The rod are 1.7 m long hanging weights 2 kg and 12 kg on ends. Where are centre of rod (distance from weight 2 kg) to be in balance?
  16. Pool
    pool If water flows into the pool by two inlets, fill the whole for 9 hours. First inlet filled pool 8 hour longer than second. How long pool is filled with two inlets separately?
  17. Bicycle wheel
    bicycle Bicycle wheel has a diameter of 60 cm. Approximately how many times the wheel rotates at 3.7 km long trip?
  18. Cakes
    cookies_2 Grandmother baked cakes. Half of its was poppy, quarter with plum jam and 16 cheesecakes. How many cakes she baked in total?
  19. 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..
  20. Water container
    water_1 Container with water weighs 1.48 kg. When we cast 75% of water container of water weight 0.73 kg. How heavy is an empty container?

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