Examples for 9th grade - page 53

  1. Line
    skew_lines It is true that the lines that do not intersect are parallel?
  2. 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?
  3. 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?
  4. Percent chaining
    meter_1 Calculate 20% from 70% from 80 km
  5. Vectors
    green For vector w is true: w = 2u+2v. Determine coordinates of vector w if u=(-8, -5), v=(18, 19)
  6. The chord
    circles_4 Calculate a chord length which the distance from the center of the circle (S, 20 cm) equals 7 cm.
  7. Work at plant
    workers_4 Handyman has vowed to do repair work at the plant for 25 days. However, work had to be shortened and therefore gained helper. Together they made all the corrections for 13 1/3 days. How long the work would take helper himself?
  8. Football league
    football_3 In the football league is 16 teams. How many different sequence of results may occur at the end of the competition?
  9. 4 pipes
    roury The tank flows out by 4 pipes in 6 hours 120 hl water. How much water flows out of 5 pipes of the same diameter in 14 hours?
  10. Uranium ore
    uran Uranium ore contains 0.2% of pure uranium and pure uranium contains 0.07% of fissile uranium. How many grams of fissile uranium contains 2200 ton of uranium ore?
  11. School year
    boys_girls At the end of the school year has awarded 20% of the 250 children who attend school. Awat got 18% boys and 23% of girls. Determine how many boys and how many girls attend school.
  12. Combinations
    circles.GIF How many different combinations of two-digit number divisible by 4 arises from the digits 3, 5 and 7?
  13. Pyramid in cube
    pyramid_in_cube In a cube with edge 12 dm long we have inscribed pyramid with the apex at the center of the upper wall of the cube. Calculate the volume and surface area of the pyramid.
  14. The book
    1438931371257-1350799500 If one day you read p pages, you will read the book 24 days. If you read each day 10 pages more, you would read a book in 16 days. How many pages have the book?
  15. Hexa prism
    hexagon Determine the volume of hex prism with edge base 4 cm. The body height is 28 cm.
  16. Trapezoid 15
    trapezoid3 Area of trapezoid is 266. What value is x if bases b1 is 2x-3, b2 is 2x+1 and height h is x+4
  17. Grid/network of cube
    siet_kocky Grid of cube has a circumference 42 mm. Calculate the surface area of the cube ...
  18. Solutions
    bilde How much 60% solution and how much 35% solution is needed to create 100 l of 40% solution?
  19. Chord 2
    circle_ Point A has distance 13 cm from the center of the circle with radius r = 5 cm. Calculate the length of the chord connecting the points T1 and T2 of contact of tangents led from point A to the circle.
  20. Tiles
    wall-tiles-img-5 How many square tiles with the content 121 cm2 has to be ordered for the paving of the square room with a side length of 2.75 meters?

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