Examples for 8th grade - page 10

  1. Crown
    2_kcs Siblings collect a 2-crowns and 5-crowns. Together have 80 coins with a total of value 310 crowns. How many saved two-crowns and how many five-crowns?
  2. 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?
  3. Rectangles
    rectangles How many rectangles with area 2832 cm2 whose sides is natural numbers are?
  4. Mountain railway
    semmering Height difference between points A, B of railway line is 38.5 meters, their horizontal distance is 3.5 km. Determine average climb in permille up the track.
  5. 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.
  6. Logik game
    logik-game Letter game Logik is a two player game, which has the following rules: 1. The first player thinks five-letter word in which no letter is not repeated. 2. The second player writes a five-letter word. 3. The first player answers two numbers - the first numbe
  7. Percent
    skiing From 117 children who participated in the ski course were 24 excellent skiers, 26 good and 26 average and the rest were beginners. Calculate this data in percentages.
  8. 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.
  9. Volume from surface area
    cube_3 What is the volume of the cube whose surface area is 96 cm2?
  10. Digging companies
    companies Company A would dig a pit for 12 days, company B for 15 days, company C for 20 days and the company D for 24 days. Work began together companies C and D, but after three days joined them other two companies. How long took to dig a pit?
  11. 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?
  12. 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?
  13. Spherical cap
    kulova_usec From the sphere of radius 12 was truncated spherical cap. Its height is 4. What part of the volume is spherical cap from whole sphere?
  14. Is equal
    Shazam Is equal following terms? ?
  15. 5 pumps
    pump Five pump to pump 3 hours 1600 hl of water. How long pumped same amount of water 4 pumps?
  16. Percent chaining
    meter_1 Calculate 20% from 70% from 80 km
  17. Sales off
    sweater If a sweater sells for $ 12 after a 25% markdown, what was its original price?
  18. Pediatrician
    doctor Pediatrician this month of 21 working days takes 3 days holidays. What is the probability that on Monday will be at work?
  19. 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?
  20. Prism
    prism-square The lenght, width and height of a right prism are 18, 14 and 9 respectively. What is the lenght of the longest segment whose endpoints are vertices of the prism?

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