Examples for 9th grade - page 5

  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. River
    kongo_river Calculate how many promiles river Hudson average falls, if on section long 921 km flowing water from 1224 m AMSL to 154 m AMSL.
  3. Two workers
    Frog Two workers together execute some work in 10 days. The first worker would have done himself in 20 days. How many days would have done himself a second worker?
  4. Accidents
    nehoda-pomnik The count of accidents in 1993 caused 8009 women which is 7.1%. How many men caused the accidents?
  5. Area of RT
    right_triangle_sepia Calculate the area of a right triangle which hypotenuse has length 20 and one hypotenuse segment has lenght 15.
  6. 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
  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. Chords
    chords How many 6-tones chords (chord = at the same time sounding different tones) is possible to play within 10 tones?
  9. Cubes
    rubik_cube Cube, which consists of 27 small cubes with edge 3 dm has volume:
  10. Sale
    sale_percent If the product twice price cut by 20%, what percentage was price cut in total?
  11. Ravens
    krkavec The tale of the Seven Ravens were seven brothers, each of whom was born exactly 1.5 years after the previous one. When the eldest of the brothers was 4-times older than the youngest, mother all curse. How old was seven ravens brothers when their mother cur
  12. Wiring
    install_pipes Conduit has a cross section 222 mm. Maybe put it into 6 conductors with a cross section S2 $mm2?
  13. 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?
  14. Tetrahedral pyramid
    jehlanctyrboky What is the surface of a regular tetrahedral (four-sided) pyramid if the base edge a=23 and height v=8?
  15. Kites
    drake Boys run kite on a cable of 86 meters long. What is the kite altitude, if the angle from the horizontal plane is 77°?
  16. Acreage
    parcela What acreage has a rectangular plot whose diagonal is 34 meters long and one side has a length of 16 meters. ?
  17. Pentagon
    5gon_1 Within a regular pentagon ABCDE point P is such that the triangle is equilateral ABP. How big is the angle BCP? Make a sketch.
  18. Clock
    hodiny How many times a day hands on a clock overlap?
  19. 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?
  20. 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?

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