Examples for 7th grade (seventh) - page 19

  1. Divers
    diving 20-member group of divers carries the air for 15 hours of diving. 4 members of the expedition sick or wasn't came. How many hours is sufficient air to other divers?
  2. Grandson and granddad
    vnuk_dedo Grandson with grandpa they counted how many years have together. Their product is 365. How many years is the sum of their years.
  3. Iron fence
    fe One field of iron fence consists of 20 iron rods with square cross-section of 1.5 cm side and a long 1 meter. How much weight a field if the density of iron is 7800 kg/m3.
  4. Racer
    car_championship The first racer run at a speed 20 m/s and is 750 meters before the finish and ahead 79 meters before second competitor. At what speed must run the second racer to catch first racer at the finish line?
  5. Strawberries
    strawberries Father collects strawberries himself in 4 hours, son in 14 hours. How long will it take them along when dad comes to help son collect strawberries after 3 hours?
  6. Chicken
    sliepka I threw three chicken for a handful of grains and I noticed that it eat in a ratio of 8:7:6 and two of them grabbed 156 grains. How many grains have fought that chicken?
  7. Sawdust
    drevo_kmen_rez How many cubic centimeters of wood sawdust is created by cut the tree trunk with a diameter of 66 cm and when the gap width is 5 mm?
  8. Copper plate
    copper-sheet Copper plate length 3.2 m and width 50 cm weighs 55.42 kg. What is the plate thick, if 1 m3 of copper weighs about 8700 kg?
  9. Unions
    odbory_prdel Calculate how much money per year would go to the treasury of unions if 218 thousand employee join unions with an average net salary of 407 euros and if memberhip in union cost 1% of the net monthly salary.
  10. Cuboids in cube
    shapes How many cuboids with dimensions of 6 cm, 8 cm and 12 cm can fit into a cube with side 96 centimeters?
  11. Painter 3
    painter_2 Dad want to paint wall high 250 cm wide and 230 cm with wallpaper. How many meters must buy wallpaper if wallpaper width is 60 cm?
  12. Cube and water
    krychle_3 How many liters of water can fit into a cube with an edge length of 0.11 m?
  13. Flowerbed 2
    flowerbed Around the square flower bed in a park is sidewalk 2 m wide. The area of ​​this sidewalk is 243 m2. What is the area of the flowerbed?
  14. RT and ratio
    triangles A right triangle whose legs are in a ratio 6:12 has hypotenuse 68 m long. How long are its legs?
  15. Four-digit number
    numbers_1 Find also a four-digit number, which quadrupled written backwards is the same number.
  16. Swing
    hojdačka22 A child weighing 12 kg is sitting on a swing at a distance of 130 cm from the axis of rotation. How far away from the axis of rotation (center) must sit down his mother weighs 57 kg if she wants to be swing in balance?
  17. Trapezoid ABCD
    trapezoid_2 Calculate the perimeter of trapezoid ABCD if we know the side c=15, b=19 which is also a height and side d=20.
  18. The body
    body_cubes The body on the figure consists of cubes with an edge length 10 cm. What surface has this body?
  19. Map 2
    world_map_atlas At what scale is made map if the distance 8.2 km corresponds on the map segment 5 cm long?
  20. Water
    storm_1 On the lawn which has area 914 m2 rained 3 mm of water. How many liters of water rained?

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