Examples for 9th grade - page 12

  1. Trapezoid
    rectangular_trapezoid Are diagonals in a rectangular trapezoid perpendicular and bisect the angles?
  2. 4side pyramid
    ihlany Calculate the volume and surface of 4 side regular pyramid whose base edge is 4 cm long. The angle from the plane of the side wall and base plane is 60 degrees.
  3. Two doctors
    dr_cvach Doctor A will determine the correct diagnosis with a probability 80% and doctor B with a probability 72%. Calculate probability of correct diagnosis if patient is diagnosed by both doctors.
  4. Sequence
    arithmetic_seq In the arithmetic sequence is a1=-9, d=4. Which member is equal to the number 147?
  5. Balls
    balls_1 Ping pong balls have a diameter of approximately 3 cm. They are sold in boxes of 3 pieces: each box has the shape of a cuboid with a square base. The balls touch the walls of the box. Calculate what portion of the internal volume of the box is filled wit
  6. Pillar
    sliced_pyramid Calculate volume of pillar shape of a regular tetrahedral truncated pyramid, if his square have sides a = 13, b = 21 and height is h = 33.
  7. RT - hypotenuse and altitude
    pravy_trojuholnik Right triangle TWS has hypotenuse s=202 km and altitude to s is 99 km. How long are hypotenuse segments?
  8. Greek railwayman
    greecerails_1 Rafael works for the Slovak railways since 1987. His salary is 874 €. His colleague, Asterios works in the Greek State Railways from 2001. Earns 5670 € per month. Calculate how many times earns Asterios more than Asterios?
  9. Cylinder - A&V
    cylinder The cylinder has a volume 253. The base has a radius 5. What is the area of surface of the cylinder?
  10. Dice
    dices How many times must throw the dice, the probability of throwing at least one three was greater than 90%?
  11. Rhomboid
    parallelogram Calculate the circumference and area of the rhomboid with sides 11 and 17, with their angle 70°.
  12. Posters
    posters Column with posters in the form of a cylinder is 3.3 m high and its diameter is 1.5 m. What is the content area for which it is possible to stick posters?
  13. Football league
    football In the 2nd football league is 19 teams. How many ways can be filled first, second and third place?
  14. Moving
    movie Vojta left the house at three o'clockat 4 km/h. After half hour later went from the same place Filip by bicycle at speed 25 km/h. How long take Tilip to catch up Vojta and how far from the house?
  15. 4s pyramid
    pyramid_regular Regular tetrahedral pyramid has a base edge a=6 and collaterally edge length b=15. What is its height?
  16. Painter Pavel
    pixla_s_farbou Painter Pavel painted the fence for 20 hours and painter Petr the same fence painted for 17 h. How long should take painted the fence together?
  17. Parquet floor
    Parkett Three workers laid parquet floor for 1.957 hour. The first one would do this work alone 5 hours, the second in 9 hours. For how many hours would fulfill this work the third worker, if he worked alone?
  18. n-gon
    x-gon What is the side length of the regular 5-gon inscribed in a circle of radius 11 cm?
  19. Steeple
    church_tower Steeple seen from the road at an angle of 57°. When we zoom out to 25 meters, it is seen at an angle of 21°. What is high?
  20. Rhombus 2
    koso Calculate the area of rhombus which has a height v=48 mm and shorter diagonal u = 60 mm long.

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