Examples for 9th grade - page 35

  1. Automaker
    car_manufactury The automaker now produces daily 4 new cars more than last year so the production of 360 cars will save just one full working day. How many working days to produce 360 vehicles needed last year?
  2. Resistors
    resistors Two resistors connected in series give the resulting resistance 216Ω and 48Ω in parallel. Determine the resistance of this resistors.
  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. Tournament
    turnaj Determine how many ways can be chosen two representatives from 34 students to school tournament.
  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. 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?
  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. Shadow and light
    stin Nine meters height poplar tree has a shadow 16.2 meters long. How long shadow have at the same time Joe if he is 1,4m tall?
  9. Angle
    atan A straight line p given by the equation ?. Calculate the size of angle in degrees between line p and y-axis.
  10. Medals
    medails In how many ways can be divided gold, silver and bronze medal among 21 contestant?
  11. Words
    words How many 3 letter "words" are possible using 14 letters of the alphabet? a) n - without repetition b) m - with repetition
  12. 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 .
  13. Disinfecting solution
    desinfect How much distilled water is necessary to pour into 500 ml of 33% hydrogen peroxide solution to obtain 3% disinfecting solution?
  14. Sphere fall
    sphere How many percent fall volume of sphere if diameter fall 10×?
  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. 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?
  17. Trigonometry
    sinus Is true equality? ?
  18. Aluminum wire
    drat Aluminum wire of 3 mm diameter has a total weight of 1909 kg and a density of 2700 kg/m3. How long is the wire bundle?
  19. Permill
    permille How many permill is 978 from 84370?
  20. 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?

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