Examples for 7th grade (seventh) - page 20

  1. 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?
  2. 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?
  3. 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.
  4. 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?
  5. 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?
  6. Cube and water
    krychle_3 How many liters of water can fit into a cube with an edge length of 0.11 m?
  7. 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?
  8. RT and ratio
    triangles Right triangle whose cathetus are in a ratio 7:14 has hypotenuse 78 m long. How long are cathetus?
  9. 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?
  10. Four-digit number
    numbers_1 Find also a four-digit number, which quadrupled written backwards is the same number.
  11. Water
    storm_1 On the lawn which has area 914 m2 rained 3 mm of water. How many liters of water rained?
  12. 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.
  13. 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?
  14. Number
    sqrt_2 Is number 5.146852 irrational?
  15. Revenue
    odmena Mr. Robert and Mr. Norbert get together € 1400. The revenue split in the ratio of 4:3, depending upon each work. How many got each of them?
  16. Building base
    base_of_building Excavation for the building base is 350x600x26000. Calculate its volume in m3.
  17. Beer
    pivo Which beer is better to drink: small beer (0.3 L) for 0.67 € or large (0.5 L) for 1.81 €?
  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. Addends
    1plus1 Number 839 divide into the two addends that the first was 17 greater than 60% of the second. Determine these addends.
  20. Soil pit
    tatra Workers dug a pit cube with edge 2.5 meters. How many cars shall remove soil if the car suddenly take 4m³ of soil?

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