Examples for 9th grade - page 7

  1. Katy MO
    reporter_saved6 Kate draw triangle ABC. Middle of AB have mark as X and the center of the side AC as Y. On the side BC wants to find the point Z such that the content area of a 4gon AXZY was greatest. What part of the triangle ABC can maximally occupy 4-gon AXZY?
  2. Octahedron - sum
    8sten On each wall of a regular octahedron is written one of the numbers 1, 2, 3, 4, 5, 6, 7 and 8, wherein on different sides are different numbers. For each wall John make the sum of the numbers written of three adjacent walls. Thus got eight sums, which also.
  3. Z9–I–1
    ctverec_mo In all nine fields of given shape to be filled natural numbers so that: • each of the numbers 2, 4, 6 and 8 is used at least once, • four of the inner square boxes containing the products of the numbers of adjacent cells of the outer square, • in the cir
  4. Cubes
    rubik_cube Cube, which consists of 27 small cubes with edge 3 dm has volume:
  5. Sale
    sale_percent If the product twice price cut by 20%, what percentage was price cut in total?
  6. Circumscribing
    thales Determine the radius of the circumscribed circle to the right triangle with legs 3 cm and 3 cm.
  7. Lathe
    soustruh From the cube of edge 52 cm was lathed maximum cylinder. What percentage of the cube is left as waste after lathed?
  8. Wiring
    install_pipes Conduit has a cross section 492 mm. Maybe put it into 5 conductors with a cross section S2 $mm2?
  9. Chords
    chords How many 6-tones chords (chord = at the same time sounding different tones) is possible to play within 10 tones?
  10. Phone numbers
    old_phone How many 9-digit telephone numbers can be compiled from the digits 0,1,2,..,8,9 that no digit is repeated?
  11. Commitee
    committees A class consists of 5 males and 18 females. How many committees of 4 are possible if the committee must consist of 3 males and 1 females?
  12. Climb in percentage
    12_percent_stupanie The height difference between points A and B is 442 m. Calculate the percentage of route climbing if the horizontal distance places A, B is 6.8 km.
  13. Tetrahedral pyramid
    jehlanctyrboky What is the surface of a regular tetrahedral (four-sided) pyramid if the base edge a=23 and height v=8?
  14. Clock
    hodiny How many times a day hands on a clock overlap?
  15. Friends in cinema
    cinema_1 5 friends went to the cinema. How many possible ways can sit in a row, if one of them wants to sit in the middle and the remaining's place does not matter?
  16. Two tributaries
    bazen_2 Two tributaries of the pool fill it in 10 hours. One of the tributaries would fill 15 hours. How long would fill the first tributary?
  17. Painters
    natieraci Five painters painting the fence for eight days. How many days over will take work if paint the fence only four decorators?
  18. Estate
    semicircle Semicircle estate must be fence. The straight section has 44 meters long fence. How many meters of fence should buy?
  19. Square grid
    sit Square grid consists of a square with sides of length 1 cm. Draw in it at least three different patterns such that each had a content of 6 cm2 and circumference 12 cm and that their sides is in square grid.
  20. Lie/do not lie
    lines_and_points The function is given by the rule f(x) = -x-12. Determine whether point D[-4; 2] lies on this function. Solve graphically or numerically and give reasons for the your answer.

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