Examples for 8th grade - page 9

  1. Kites
    drake Boys run kite on a cable of 68 meters long. What is the kite altitude, if the angle from the horizontal plane is 72°?
  2. Pedestrian up-down hill
    peak Pedestrian goes for a walk first at plane at 4 km/h, then uphill 3 km/h. Then it is in the middle of the route, turns back and goes downhill at speed 6 km/h. Total walk was 6 hours. How many kilometers went pedestrian?
  3. Medians
    medias_triangle Calculate the sides of a right triangle if the length of the medians to the legs are ta = 21 cm and tb=12 cm.
  4. Described
    desc_circle Calculate perimeter of the circle described by a triangle with sides 478, 255, 352.
  5. Rotation
    cone_1 Right triangle with legs 14 cm and 20 cm rotate around longer leg. Calculate the volume and surface area of the formed cone.
  6. VAT
    Tax John paid 100 Euros in store for purchase. Calculate value added tax (VAT), which paid in purchase, if the VAT rate is 20%.
  7. Floating barrel
    floating_barrel Barrel (cylinder shape) floats on water, top of barrel is 8 dm above water and the width of surfaced barrel part is 23 dm. Barrel length is 24 dm. Calculate the volume of the barrel.
  8. Circular pool
    arc_open The base of pool is circle with a radius r = 10 m excluding circular segment that determines chord length 10 meters. Pool depth is h = 2m. How many hectoliters of water can fit into the pool?
  9. Guests
    hostia How many ways can 8 guests sit down on 10 seats standing in a row?
  10. Trapezoid
    trapezoid_1 Calculate area of trapezoid ABCD with sides |AD|= 69 cm, |DC|=35 cm, |CB|=21 cm, |AB|=29 cm..
  11. The cyclist
    cyclist The cyclist went from village to town. First half of journey went at 20 km/h. The second half of the journey, which mostly fell, went at 39 km/h. All journey took 88 minutes. Calculate the distance from the village to the town.
  12. Air mass
    airbaloon What is the weight of the air in a classroom with dimensions 10 m × 0 m × 2.5 m ? The air density is 1.293 kg/m3.
  13. Quarter circular
    quarter_circle The wire that is hooked around the perimeter of quarter-circular arc has length 3π+12. Determine the radius of circle arc.
  14. Triangle
    eq_triangle Can be rectangular triangle equilateral?
  15. R Trapezium
    Trapezium_example Rectangular trapezium has bases 18 and 11 and area 28 cm2. What is its perimeter?
  16. Angles
    rhombus_1 Determine the interior angles of a rhombus with area 319.1 cm2 and perimeter 72 cm.
  17. Ladder
    rebrik_1 Ladder 8 m long is leaning against the wall. It foot is 1 m away from the wall. In which height ladder touch the wall?
  18. Car range
    Lupo_3L_TDI.JPG Calculate the maximum range of car, if you can spend 10 euros, price of diesel is 1.55 Eur/l and car consumption is 3 l/100 km.
  19. One half
    one_half One half of ? is: ?
  20. 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 3.9 %, in the second 6%, in the third 4.7% and in the fourth 5.5%. Then tsar was failed in election. Calculate the aver

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