Problems for 7th grade (seventh)

  1. Winch
    bubon The steel rope has a diameter of 6mm and a length of 20m. We are winding on drum width 60mm, starting diameter 50mm. What is the final diameter after winding?
  2. Delayed clock
    clock-night-schr Michael put a new battery into his watch at midnight. However, they are 5 seconds late each minute. How many hours does the watch show in 24 hours?
  3. Iceberg
    ice What is the surface area of 50 cm iceberg (in the shape of a cuboid) that can carry a man with luggage with a total weight of 120 kg?
  4. Tourist
    tourist A tourist walked an average speed of 3.5 km/h route in 6 hours. Calculate how many hours he would have passed at an average speed of 5.5 km/h.
  5. Geometric plan
    map_1 At what scale the building plan if one side of the building is 45m long and 12mm long on a plan?
  6. Down syndrome
    gene Down syndrome is one of the serious diseases caused by a gene mutation. Down syndrome occurs in approximately every 550-born child. Express the incidence of Down's syndrome in newborns at per mille.
  7. Cube into cylinder
    cube_sphere_in If we dip a wooden cube into a barrel with a 40cm radius, the water will rise 10 cm. What is the size of the cube edge?
  8. Iron pole
    pole The iron pole is in the ground 2/5 of its length, partly above the ground 1/3 is yellow, and the unpainted section is 6 m long. How long is the entire column?
  9. Cook on gas
    lpg The gas cylinder will last for 30 weekends for 2 hours of daily cooking. How many days will we be able to cook on a new cylinder when we cook 3 hours a day?
  10. Dance group
    dancers The dance group formed groups of 4, 5, and 6 members. Always one dancer remains. How many dancers were there in the whole group?
  11. Barter
    kozky There is exchange trade on the market. We know that for two sheepskins we get three goat skins. We also know that for six rabbits skins we get four goat skins. How many rabbit's skins we get for four sheepskins?
  12. Temperature change
    teplomer_31 The mean temperature change is -3.2°F per day for five days. What is the total change over the five day period?
  13. Last page
    books_44 Two consecutive sheets dropped out of the book. The sum of the numbers on the sides of the dropped sheets is 154. What is the number of the last page of the dropped sheets?
  14. Prism 4 sides
    kvader11_5 Find the surface area and volume four-sided prism high 10cm if its base is a rectangle measuring 8 cm and 1.2dm
  15. The King
    gold_4 The King wants to divide his sons equally. He has 42 rubies and 45 diamonds. How many sons and how will they share them?
  16. Four workers
    wood_6 Four workers will lay the floor of the gym in six hours. After an hour of working together, one of the workers left to the doctor. How long before the remaining three workers finish their work?
  17. Area of rectangle
    rectangle_24 How many times will increase the area of the rectangle, if we increase twice the length and at the same time we decrease the width by the half?
  18. MG=7x-15,
    segment_6 MG=7x-15, FG=33, x=? Point M is the midpoint of FG. Find unknown x.
  19. Midpoint 6
    segment_5 FM=8a+1, FG=42, a=? Point M is the midpoint of FG. Find unknown a.
  20. Midpoint 5
    segment_4 FM=3x-4, MG=5x-26, FG=? Point M is the midpoint of FG. Use the given information to find the missing measure or value.

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