Examples for 7th grade (seventh)

  1. Building
    wood_3 At the building, we divided 240 boards into two piles in a 5: 3 ratio. How many were fewer boards in the lower pile?
  2. Cubes into cuboid
    cubes_21 How many 12 centimeter cubes fit into the block (cuboid) with 6dm, 8,4dm and 4,8?
  3. Shadow of tree
    stromcek_3 Miro stands under a tree and watching its shadow and shadow of the tree. Miro is 180 cm tall and its shade is 1.5 m long. The shadow of the tree is three times as long as Miro's shadow. How tall is the tree in meters?
  4. Surface area 6
    prism3s Find the surface area of a prism whose bases are right triangles with sides of length 3, 4, and 5 inches and a height of 8 inches. Include a sketch
  5. Three pumps
    watertank_2 The water tank is emptied with the first pump in 6 hours, with the second pump in 2 hours. In order to be emptied in 1 hour, all three pumps had to be started at once. How long will take tank be emptied by only the third pump?
  6. Three 43
    penize_49 Three brothers inherited a cash amount of 62,000 and they divided it among themselves in the ratio of 5:4:1. How much more is the largest share than the smallest share?
  7. Water flow 2
    water3_9 How many litres of water will flow in 7 minutes from a cylindrical pipe 1 cm in diameter, if the water flows at a speed of 30 km per hour
  8. Rectangular prism
    kvader11_2 If i have a rectangular prism with a length of 1,000 cm, width of 30 cm and a height of 50 cm, what is the volume?
  9. Mysterious number
    fun3_9 The magician thinks the number: "The mysterious number is first divided by minus five, dividing the result by three, multiplying the number by ten, and dividing the resulting number by minus four. This gives result 5. Can you reveal the mysterious number
  10. Thunderstorm
    storm-012_1 The sound travels 1 km in about 3 seconds. How far is the storm if there is a time interval of 8 seconds between lightning and thunder?
  11. Seven
    post_1 Seven friends agree to send everyone a holiday card. How many postcards were sent?
  12. Report 2
    skola_4 A School reports students to teacher ratio of 6:1. If there are 45 teachers in the School, how many students are there?
  13. Simple sequence
    sequence_geo_6 Continue with this series of numbers: 1792,448, 112, _, _
  14. Two discounts
    mince_6 The MP4 player cost 960 CZK, the price was twice gradually reduced in the ratio 4: 3: 3/2. How much did the player cost after the second discount?
  15. Dinosaurs
    dino More than 30 and less than 60 dinosaurs have met at the pond. A quarter of them bathed and 1/7 saws and the rest gripped. How many were at the pond? How many were there?
  16. Dropped sheets
    books_26 Three consecutive sheets dropped from the book. The sum of the numbers on the pages of the dropped sheets is 273. What number has the last page of the dropped sheets?
  17. Twenty
    rabbits_1 Twenty rabbits are put in 4 cells so that there are different number of rabbits in each cell contains at least 3 rabbits. What is the largest possible number of rabbits in one cell
  18. How much
    woord_1 How much money will we pay for 20 planks 4m long, 15cm wide and 26mm thick when 1m³ of wood costs 4500kč?
  19. Rhombus 29
    rhombus3_2 One of the diagonals of a rhombus is equal to a side of the rhombus. Find the angles of the rhombus.
  20. Pool tiles
    bazen_5 The pool is 25m long, 10m wide and 160cm deep. How many m2 of tiles will be needed on the walls and the pool? How many pieces of tile are needed when 1 tile has a square shape with a 20cm side? How much does it cost when 1m2 of tiles costs 258 Kc?

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