Examples for 8th grade - page 42

  1. Driving school
    bmw-autoskola Driving final exam involving 17 attendants. The exam consists of three parts. 4 fails at test (quiz) and 3 students fails on car skills test on playground (slalom between the cone). The practical part of the test - driving in town in the real traffic - al
  2. Louvers
    zaluzie The company charges for office equipment louvers total 244 Eur. From the delivery bill is obvious that the louvers are 73 Eur expensive than their installation. What percentage of the total charged is the installation of louvers?
  3. Monty Hall
    Monty_open_door Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, say No. 3, which has a goat. W
  4. Mean
    integrales if the mean of the set of data 10, 13, 8, 18, 20, 17, 19, 3, 10, 8, 8, 3, 12, 15, 14, 4, 20, 19, x is 24.36, what is the value of x?
  5. Tape
    mg Video is 250% more expensive than tape recorder. How many percent is tape recorder less expensive than video?
  6. Free fall
    volny_pad Stephen fall from height 5 m. Calculate the speed he hit the ground when falling with acceleration g = 9.81 m/s2
  7. Pipe
    1pipes How long is the pipe with an outside diameter of 0.55 m if his coloring consumed 43 kg of color. 1 kg of color coverage is 10 m2.
  8. Rotating cone II
    cone Calculate area of surface of rotating cone with base radius r=7 cm and height h=17 cm.
  9. Circle and angle
    arc What is the length of the arc of a circle with radius r = 138 cm with cental angle 2.07 rad?
  10. Hollow sphere
    Xmas_ball Calculate the weight of a hollow brass sphere (density 8.5 g/cm3), if the outer diameter is 10 cm and wall thickness is 3 mm.
  11. Cube - angles
    cube_diagonal_1 Calculate angle between the wall diagonal and cube base. Calculate the angle between the cube body diagonal and cube base.
  12. Right triangle Alef
    r_triangle The perimeter of a right triangle is 132 cm, the hypotenuse is 55 cm long. Determine the lengths of the legs.
  13. Triangular prism
    prism3 Calculate the volume and surface of the triangular prism ABCDEF with base of a isosceles triangle. Base's height is 16 cm, leg 10 cm, base height vc = 6 cm. The prism height is 9 cm.
  14. Six years
    children_9 In six years Jan will be twice as old as he was six years ago. How old is he?
  15. Trapezoid
    lichob_2_1 How long are the trapezoid bases with area 24 cm2 and height 3 cm. One base is 3 times longer than the shorter.
  16. Rhombus
    kosostvorec_6 If we increase the rhombus side by 2.4 cm; its perimeter is 20 cm. How long was the side of the rhombus?
  17. Apples
    jablka_4 Apples I picked 600 kg this year. Autumn's apples was 4 times more than the summer. How many kg's I picked the summer and how much winter apples?
  18. Rings groups
    venn 27 pupils attend some group; dance group attends 14 pupils, 21 pupils sporty group and dramatic group 16 pupils. Dance and sporting attend 9 pupils, dance and drama 6 pupil, sporty and dramatic 11 pupils. How many pupils attend all three groups?
  19. Unknown number 7
    percents2_9 16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
  20. Grass
    minutes_clock Peter and Stano lawn grass for 3 hours 12 minutes. How long would it take to Peter if Stano lawn grass himself for 384 minutes.

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