Examples for 9th grade - page 34

  1. The angle of lines
    lines Calculate the angle of two lines y=x-21 and y=-2x+14
  2. Rectangular triangles
    r_triangles The lengths of corresponding sides of two rectangular triangles are in the ratio 2:5. At what ratio are medians relevant to hypotenuse these right triangles? At what ratio are the contents of these triangles? Smaller rectangular triangle has legs 6 and 8 c
  3. Angles of the triangle
    angles ABC is a triangle. The size of the angles alpha, beta are in a ratio 4: 7. The angle gamma is greater than the angle alpha by a quarter of a straight angle. Determine angles of the triangle ABC.
  4. Brass tube
    Ms_trubka The outer perimeter of brass tube (ρ = 8.5 g/cm3) is 38 cm. Its mass is 5 kg, length 54 cm. What is the pipe wall thickness?
  5. Maple
    tree_javor Maple peak is visible from a distance 3 m from the trunk from a height of 1.8 m at angle 62°. Determine the height of the maple.
  6. Tournament
    turnaj Determine how many ways can be chosen two representatives from 34 students to school tournament.
  7. Reflector
    lamp Circular reflector throws light cone with a vertex angle 49° and is on 33 m height tower. The axis of the light beam has with the axis of the tower angle 30°. What is the maximum length of the illuminated horizontal plane?
  8. Angle
    atan A straight line p given by the equation ?. Calculate the size of angle in degrees between line p and y-axis.
  9. Trigonometry
    sinus Is true equality? ?
  10. Railways - golden parachutes
    pavel-kravec_kdh As often happens in Slovakia habit, the state's financial institution which takes from poverty and gorilas give. A hardworking punishing taxes. Let's look at a short work of director Railway Company ZSSK - Mgr . P. K. : 18 months 'work' as director .
  11. Medals
    medails In how many ways can be divided gold, silver and bronze medal among 21 contestant?
  12. Cube wall
    cubes_16 Calculate the cube's diagonal diagonal if you know that the surface of one wall is equal to 36 centimeters square. Please also calculate its volume.
  13. Painters
    painters The first team of painters would paint bridge in 15 days, the second in 10 days. After 3 days of working together second team goes out and continue only first team. How many days took second team to finish painting the bridge?
  14. Words
    words How many 3 letter "words" are possible using 14 letters of the alphabet? a) n - without repetition b) m - with repetition
  15. Circles
    pyt_theorem In the circle with a radius 7.5 cm are constructed two parallel chord whose lengths are 9 cm and 12 cm. Calculate the distance of these chords (if there are two possible solutions write both).
  16. Two cars
    car_racing Car A1 goes at average speed of 106 km/h and the second car A2 goes at 103 km/h. How many second will it take car A1 to circulate car A2? Assume that both cars are 5 meters long and the safety gap between cars is 1.5 meters.
  17. The camp
    diary At the end of the camp a 8 friends exchanged addresses. Any friend gave remaining 7 friends his card. How many addresses they exchanged?
  18. Sphere fall
    sphere How many percent fall volume of sphere if diameter fall 10×?
  19. Permill
    permille How many permill is 978 from 84370?
  20. Against each other
    Lotus_Esprit From two points A, B distant 23 km at the same time started two cars against each other at speeds 41 km/h and 65 km/h. How long does cars meet and what distance passes each of them?

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