Examples for 8th grade - page 18

  1. Raffle
    tombola How many raffle tickets must be purchased by Peter in raffle with issued 200 tickets if he wants to be sure win at least 3 price? In the raffle draws 30 prices.
  2. Cylinder
    cylinder The cylinder surface is 139 dm2, its height is equal to the radius of the base. Calculate height of this cylinder.
  3. Camel
    camels Camel owner wants to get out of the city into oasis. He bought 3000 bananas, which wants to sell in oasis. However oasis from the city divided 1,000 kilometers of desert. Camel can carry at one time up to 1000 bananas, and for every kilometer traveled, ea
  4. Pool
    inlet Pool is filled with two water supply. The first supply fill pool for nine hours, the second for six hours. How many hours will take fill the pool when the water flows in through the first supply 3 hours and then we will open a second supply?
  5. Resort
    rekreace In a completely crowded resort was 30% from the Czech Republic quarter visitors were from Slovakia and the rest 135 came from Germany. What capacity have resort?
  6. Five-digit
    cards Find all five-digit numbers that can be created from numbers 12345 so that the numbers are not repeated and then numbers with repeated digits. Give the calculation.
  7. Pumps
    number-1 First pump flows 16 liters per second into the basin by the second pump 75% of the first and by third pump half more than the second. How long will take fill basin by all three pumps simultaneously volume 15 m3 (cubic meters)?
  8. Tank and water
    chemickelaboratorium1 Cylindrical tank were poured with 3.5 liters of water. If tank base diameter is 3 dm, how height is water level in?
  9. Cuboid
    cuboid_3 Cuboid ABCDEFGH with 10 cm height has a base edge length 6 cm and 8 cm. Determine angle between body diagonal and the base plane (round to degrees).
  10. Segments
    segments Line segments 52 cm and 7.6 dm long we divide into equal parts which lengths in centimeters is expressed integer. How many ways can we divide?
  11. Bottle
    bottle Bottle with wine costs 61 USD. Wine is 11 USD more expensive than the empty bottle. How much is the bottle itself?
  12. Skier
    skiing_1 At this point, the first skier lead 14 km before the second skier and travels at a constant speed 13 km/h. The second skier rides at 19 km/h. How long take him to catch up the first?
  13. Workers
    two_workers Workers A and B will done work together for 20 days. They worked together 18 days. Then A worker became ill and worker B finish the job alone for 11 days. If every worker was working alone, how many days took whole work for worker A and B?
  14. Homework
    family Mother and Kate together weigh 27 kg more than the father. Father weighs 8.4 kg more than mother. Father weight 35 kg more than Kate. Determine weights of father mother and Kate.
  15. Hostel
    student Students are accommodated in 17 rooms. Rooms were 4 and 6 bed. How many rooms in which type occupied 88 children there?
  16. Sea water
    sea_1 Seawater contains about 6.8% salt. How many dm3 of distilled water we must pour into 30 dm3 of sea water to get water with 1.9% salt?
  17. Building
    Taipei_101 How high is the building that throws horizontal shadow 58.5 m long at angle 36°36'?
  18. Quarter circular
    quarter_circle The wire that is hooked around the perimeter of quarter-circular arc has length 14π+56. Determine the radius of circle arc.
  19. Shots
    broky 2000 lead shots with diameter 2 mm is decanted into a ball. What is it diameter?
  20. Water inlets
    pipe Inlet valve with a flow rate of 12 liters per second is filled tank for 72 minutes. How long take to fill full tank if we open one more such valve half an hour after?

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