Examples for 7th grade (seventh) - page 30

  1. Right triangle
    triangles_1 Right triangle ABC with side a = 19 and the area S = 95. Calculate the length of the remaining sides.
  2. Tons of coal
    coal_2 Coal hopper has a capacity of 285 liters. How many tons is it? The bulk density of coal is 916 kg/m3.
  3. Slovak broad track
    sirokorozchodna Once upon a time, we learned in school that the Russians have "wider" tracks than our, because they have less tolerable ground. In truth, decide olny area of sleepers, no track gauge. Calculate how many millimeters, our track 1435 mm different from the R
  4. Rabbits
    zajace_1 Michael breeding rabbits. His 7 rabbits will eat 98 feed rations for 7 days. How many equal portions of feed should be eat 5 rabbits in 6 days?
  5. Czech crowns
    KC.JPG Small Petra save money. Grandfather give her 10 crowns. Petra asked his older sister let her calculate how much he has saved up. Sister told her that he has less than 30 crowns. If the sum is divided by three left one crown. If the sum is divided by the f
  6. Average
    gaussian Average of 7 numbers is 65. What is its sum?
  7. Road - permille
    18procent 5 km long road begins at an altitude 500 meters above sea level and ends at a altitude 521 ASL. How many permille road rises?
  8. Office rent
    futbal-stadion For rent 1m2 of office space is paid €165 per year. How much is the annual rent for an office as big as a football field with dimensions 71.5 m and 102.5 m?
  9. Rectangle and circle
    rectangle_circle_desc The rectangle ABCD has side lengths a = 40 mm and b = 30 mm and is circumscribed by a circle k. Calculate approximately how many cm is circle long.
  10. Trees
    trees_1 Loggers wanted to seed more than 700 and less than 800 trees. If they seed in rows of 37, left them 8 trees. If they seed in rows of 43, left the 11 trees. How many trees must seed ?
  11. Oil tank and pipes
    oil_tank The underground oil tank can be filled by two oil pipelines. The first is filled in 72 hours and the second in 48 hours. How many hours from the moment when first pipeline began to fill the oil is it necessary to start filling it with the second to fill in
  12. Machines 2
    machine_1 2 machines for 50 hours produces 2,000 products. How many machines need to buy to make in 30 hours 15,000 products?
  13. Octagon from rectangle
    8gon From tablecloth rectangular shape with dimensions of 4 dm and 8 dm we cuts down the corners in the shape of isosceles triangles. It thus formed an octagon with area 26 dm2. How many dm2 we cuts down?
  14. Chicken and rabbits (classic)
    zajace Grandmother breeding chickens and rabbits. It found that the yard has 35 heads and 108 legs. How many chickens and rabbits breeding in the yard?
  15. Water in body
    Water-in-human-body Water in the human organism of all the compounds represented, constitutes about 3/5 of the total weight. How many kilograms of water is in your body when you weigh 67 kg?
  16. Total displacement
    stroke_bore_engine Calculate total displacement of the 4-cylinder engine with the diameter of the piston bore B = 6.6 cm and stroke S=2.4 cm of the piston. Help: the crankshaft makes one revolution while the piston moves from the top of the cylinder to the bottom and back.
  17. Two pumps
    nadrz_4 The first pump fills the tank in 24 hours second pump in another 40 hours. For how long will take fill the tank if operate both pumps at the same time?
  18. Deposit 3
    interest_money After a year had Martin on bank account € 2028. What was the interest rate when the initial deposit was € 1879?
  19. Clocks
    clocks How long track travel the second hand in 46 hours, the end of which is 4 cm long.
  20. Tractors
    tractor 6 tractors started plowing the field that them together take 12 days. Agronomist hesitates to A) after 2 days to withdraw 2 tractors, or B) after 3 days to withdraw 3 tractors. Help him which of these two cases will be plowing done sooner.

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