Examples for 8th grade - page 22

  1. Apartments
    panelak Apartment on the first floor was 10% more expensive than the same apartment on the second floor. The difference was 105 Kc annually. Calculate the annual rent of the apartment in the first floor and from apartment on the second floor.
  2. Pizza
    pizza_1 A school survey found that 9 out of 16 students like pizza. If 5 students are chosen at random, what is the probability that all 5 students like pizza?
  3. Rectangle
    rectangles_1 The perimeter of the rectangle is 22 cm and content area 30 cm2. Determine its dimensions, if the length of the sides of the rectangle in centimeters is expressed by integers.
  4. Trains for people
    757_rusen It is said that the train is synonymous to delay. Calculate the average speed of travel by train long 50 km, with regular train leave at 6:05 and arrive at 7:20, but train is late and has departure at 9:52 and arrive at 11:05.
  5. Height
    equilateral_triangle Calculate height of the equilateral triangle if its perimeter is 54?
  6. Two runners
    sprinters_1 Two runners ran simultaneously towards each other from locations distant 21 km. The average speed of the first runner was 1/7 higher than the average speed of the second runner. How long should each ran a 21 km, if you know that they meet after 77 minute
  7. Map - climb
    Lanovka_na_skalnate_pleso On the map of High Tatras in scale 1:25000 are cable car stations in the Tatranska Lomnica and in the Skalnate Pleso with distance 156 mm. Altitude of this stations are 944 m and 1755 m. What is average angle of climb of this cable car track?
  8. Concrete pipe
    concrete_pipe Concrete pipe is cylindrical with an inner diameter 130 cm and outer 142 cm. Calculate the surface of the concrete pipe, if it is 6 m long.
  9. Degrees to radians
    angle Convert magnitude of the angle α = 618°40'29" to radians:
  10. Task
    cube_1 I have homework. The cube has an edge 11 cm long and I must find wall and body diagonal.
  11. Rectangle diagonals
    rectangle_diagonals_1 It is given rectangle with area 24 cm2 a circumference 20 cm. The length of one side is 2 cm larger than length of second side. Calculate the length of the diagonal. Length and width are yet expressed in natural numbers.
  12. 9.A
    exam 9.A to attend more than 20 students but fewer than 40 students. A third of the pupils wrote a math test to mark 1, the sixth to mark 2, the ninth to mark 3. No one gets mark 4. How many students of class 9.A wrote a test to mark 5?
  13. Tiles
    dlazdice From how many tiles 20 cm by 30 cm we can build a square of maximum dimensions, if we have maximum 390 tiles.
  14. Kids
    kids How many different ways can sit 5 boys and 5 girls in line, if girls want to sit on the edge?
  15. Tractors
    tractor_2 Six tractors plowing the field for 8 days. After two days, two tractors broke down. How many days were prolonged work in the field?
  16. Lunch for free
    Gastrolistky Gastro ticket are "free" and therefore they should be retained. This think many employees in Slovakia. Calculate how much money employee yearly earn if he get 217 gastro tickets of 2.7 € and you know that the company issuing gastro tickets get 4.4% fee of
  17. Salary
    platy Calculate equivalent annual salary to hourly salary $ 29. Assume a 40-hour work week.
  18. Cable car 2
    lanovka_1 Cable car rises at an angle 39° and connects the upper and lower station with an altitude difference of 345 m. How long is the track of cable car?
  19. Sphere - parts
    odsek_vusek Calculate the area of a spherical cap, which is part of an area with base radius ρ = 10 cm and a height v = 2.7 cm.
  20. Iron sphere
    sphere_1 Iron sphere has weight 100 kg and density ρ = 7600 kg/m3. Calculate the volume, surface and diameter of the sphere.

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