Examples for 8th grade - page 8

  1. Pediatrician
    doctor Pediatrician this month of 21 working days takes 3 days holidays. What is the probability that on Monday will be at work?
  2. Meadow
    ovce-miestami-baran On the meadow grazing horses, cows and sheep, together less than 200. If cows were 45 times more, horses 60 times more and sheep 35 times more than there are now, their numbers would equall. How many horses, cows and sheep are on the meadow together?
  3. Rhombus and inscribed
    rhombus_2 Rhombus has side a = 72 cm, the radius of the inscribed circle is r = 10 cm. Calculate the length of its two diagonals.
  4. Rectangle - sides ratio
    rectangle_2 Calculate area of rectangle whose sides are in ratio 1:7 and perimeter is 735.
  5. Cube zoom
    krychle_1 How many percent we increase volume and surface of cube, if we magnify its edge by 61%.
  6. Trapezoid
    trapezoid_1 Calculate area of trapezoid ABCD with sides |AD|= 33 cm, |DC|=15 cm, |CB|=19 cm, |AB|=13 cm..
  7. 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.
  8. Rotation
    cone_1 Right triangle with legs 9 cm and 16 cm rotate around longer leg. Calculate the volume and surface area of the formed cone.
  9. Triangle
    eq_triangle Can be rectangular triangle equilateral?
  10. 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.
  11. Air mass
    airbaloon What is the weight of the air in a classroom with dimensions 5 m × 2 m × 3.1 m ? The air density is 1.293 kg/m3.
  12. The cyclist
    cyclist The cyclist went from village to town. First half of journey went at 19 km/h. The second half of the journey, which mostly fell, went at 33 km/h. All journey took 67 minutes. Calculate the distance from the village to the town.
  13. MO SK/CZ Z9–I–3
    ball_floating_water John had the ball that rolled into the pool and it swam in the water. Its highest point was 2 cm above the surface. Diameter of circle that marked the water level on the surface of the ball was 8 cm. Determine the diameter of John ball.
  14. Inflation
    tsar Once upon a time, tsar owned a money printer and printed and printed. The result of printing money prices went up,in the first year 5.9 %, in the second 2.4%, in the third 5.9% and in the fourth 5.7%. Then tsar was failed in election. Calculate the av
  15. Car range
    Lupo_3L_TDI.JPG Calculate the maximum range of car, if you can spend 25 euros, price of diesel is 1.55 Eur/l and car consumption is 6.4 l/100 km.
  16. R Trapezium
    Trapezium_example Rectangular trapezium has bases 17 and 7 and area 80 cm2. What is its perimeter?
  17. Train and car
    car_vs_train The train and the car started at a constant speed to journey. When the train travels 78 km, the car travels 64 km. How many km travels the train when the car travels 78 km?
  18. Saving
    cars Kevin save € 4620 to buy a car. Yet it lacks save 65% of the car price. How much is the car?
  19. Angles
    rhombus_1 Determine the interior angles of a rhombus with area 240.6 cm2 and perimeter 64 cm.
  20. Guests
    hostia How many ways can 7 guests sit down on 9 seats standing in a row?

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