Examples for 9th grade - page 51

  1. Water well
    studna Drilled well has a depth 20 meters and 0.1 meters radius. How many liters of water can fit into the well?
  2. Stamps and albums
    stamp Michail has in three albums stored 170 stamps. In the first album, there are 14 more than in the second and in the second is by 1/5 less than in the third. How many stamps are in the first album?
  3. Crates 2
    bedny In 6 crates is 45 kg of apples In  5 crates is equally In 1 in crate is 3 kg more How many kilograms in each crate?
  4. Double-track
    vlak_1 On double-track express met with a freight train. Express travel at speed 72 km/h, a freight train at speed 36 km/h. After what time period will be from 9 km apart?
  5. Annual income
    income The annual incomes (in thousands of $) of fifteen families is: 60, 80, 90, 96, 120, 150, 200, 360, 480, 520, 1060, 1200, 1450, 2500, 7200 Calculate harmonic and geometric mean.
  6. High wall
    mur I have a wall 2m high. I need a 15 degree angle (upward) to second wall 4 meters away. How high must the second wall?
  7. Prism
    prism Base of perpendicular triangular prism is a right triangle with cathetuses 4.5 cm and 6 cm. What is the surface of the prism, if its volume of 54 cubic centimeters.
  8. Fraction
    polynomial For what x expression ? equals zero?
  9. Cleaners
    clean Milan would clean up the room for 2.5 hours, Eric would take 10 hours. How long they swept the room together?
  10. Bob and Bobek
    bob_a_bobek At 10h 20min runs Bobek from hat at average speed 12 km/h. At what time must run out Bob at speed 18 km/h to catch him 9 kilometers from the hat?
  11. Win in raffle
    tombola_1 The raffle tickets were sold 200, 5 of which were winning. What is the probability that Peter, who bought one ticket will win?
  12. Tower model
    tower Tower height is 300 meters, weight 8000 tons. How high is the model of the tower weight 1 kg? (State the result in the centimeters). The model is made from exactly the same material as the original no numbers need to be rounded. The result is a three-digi
  13. Reduce of the volume
    cubes Calculate how many % reduce the volume of the cube is we reduced length of each edge by 10%.
  14. Powers
    1power Express the expression ? as the n-th power of the base 7.
  15. V - slope
    verticals The slope of the line whose equation is 8x +8 = 0 is
  16. Statistics
    lines_globe The sum of all deviations from the arithmetic mean of the numerical sequence 1, 7, 7, 26, 43, 47, 80, 96, 113, 120 is:
  17. Speedometer
    lotus The speedometer of a car reads 78 km/h. It's accurate to within 4.2% What is the maximum possible error?
  18. Tiles
    dlazba How much you will pay CZK for laying tiles in a square room with a diagonal of 8 m if 1 m2 cost CZK 420?
  19. Chords
    chords How many 6-tones chords (chord = at the same time sounding different tones) is possible to play within 10 tones?
  20. Waiting room
    fly In the waiting room are people and flies. Together they have 15 heads and 50 legs (fly has 6 legs). How many people and flies are in the waiting room?

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