Examples for 9th grade - page 6

  1. 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.
  2. Accidents
    nehoda-pomnik The count of accidents in 1993 caused 8009 women which is 7.1%. How many men caused the accidents?
  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. Acreage
    parcela What acreage has a rectangular plot whose diagonal is 34 meters long and one side has a length of 16 meters. ?
  5. Lathe
    soustruh From the cube of edge 52 cm was lathed maximum cylinder. What percentage of the cube is left as waste after lathed?
  6. Chords
    chords How many 6-tones chords (chord = at the same time sounding different tones) is possible to play within 10 tones?
  7. Sale
    sale_percent If the product twice price cut by 20%, what percentage was price cut in total?
  8. Cubes
    rubik_cube Cube, which consists of 27 small cubes with edge 3 dm has volume:
  9. Wiring
    install_pipes Conduit has a cross section 222 mm. Maybe put it into 6 conductors with a cross section S2 $mm2?
  10. 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
  11. Copiers
    images Three copiers will do the same in an hour k copies. How many copies would be done in an hour by four such copiers? ?
  12. 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?
  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. 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. 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?
  17. 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?
  18. 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.
  19. 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.
  20. Circumscribing
    thales Determine the radius of the circumscribed circle to the right triangle with legs 3 cm and 10 cm.

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