Examples for 8th grade - page 12

  1. Eiffel Tower
    eiffel_tower Eiffel Tower in Paris is 300 meters high, is made of steel. Its weight is 8000 tons. How tall is the tower model made ​​of the same material, if it weigh is 4.8 kg?
  2. Cleaners
    clean Milan would clean up the room for 2.5 hours, Eric would take 10 hours. How long they swept the room together?
  3. Apprentice
    ucen Worker and apprentice execute the work for 6 hours. Worker performs himself in 10 hours. How long do the work of an apprentice?
  4. Olympics
    olimpiada-medaliile In how many ways can be placed 6 athletes on the podium at the Olympics? Depend on the color of the metal.
  5. Garden
    garden_1 Area of square garden is 6/7 of triangle garden with sides 96 m, 60 m and 60 m. How many meters of fencing need to fence a square garden?
  6. Rhombus
    rhombus Calculate the perimeter and area of ​​rhombus whose diagonals are 15 cm and 27 cm long.
  7. Motion problem
    dragway From Bratislavy to Martina go car at speed 83 km/h. From Martina to Bratislavy go another car at speed 62 km/h. How many minutes before the meeting will be cars 21 km away?
  8. Nuts
    nuts How many we must have at least nuts if we can equally divide it to 10 children, 14 children or 19 children and any nut left?
  9. Apples and pears
    hrusky2 Mom divided 24 apples and 15 pears to children. Each child received the same number of apples and pears - same number as his siblings. How many apples (j=?) and pears (h=?) received each child?
  10. Solutions
    bilde How much 60% solution and how much 35% solution is needed to create 100 l of 40% solution?
  11. Spartakiada
    spartakiada_1 Practitioners lined up in rectangle with row with four, five or six exercisers, one always missing to full rectangle. How many exercisers were on the field, if they have estimated not been more than 100?
  12. Cyclist
    1cyclist Cyclist goes uphill 1 km for 6.3 minutes and downhill minutes for 2.1 minutes, both applied to the pedals same force. How long he pass 1 km by plane?
  13. Rhombus
    rhomus_circle It is given a rhombus of side length a = 11 cm. Touch points of inscribed circle divided his sides into sections a1 = 6 cm and a2 = 5 cm. Calculate the radius r of the circle and the length of the diagonals of the rhombus.
  14. Rectangles
    rectangles How many rectangles with area 2832 cm2 whose sides is natural numbers are?
  15. 5 pumps
    pump Five pump to pump 3 hours 1600 hl of water. How long pumped same amount of water 4 pumps?
  16. Ladder
    studna 7.4 meters long ladder is leaning against the wall of the well and its lower end is 1.1 meters from this wall. How high from the bottom of a well is the top edge of the ladder?
  17. Mr. Vojta
    penize Mr. Vojta put in the bank 35000 Kč.After a year bank him credited with interest rate of 2% of the deposit amount. How then will Mr. Vojta in the bank?
  18. Sales off
    sweater If a sweater sells for $ 12 after a 25% markdown, what was its original price?
  19. Welders
    svarec Welder do the job for six hours, the second one for 8 hours. How long do the job third welder if all together can do job in 2 hours?
  20. Percent chaining
    meter_1 Calculate 20% from 70% from 80 km

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