Examples for 9th grade - page 5

  1. Transforming cuboid
    cube Cuboid with dimensions 12 cm, 20 and 8 cm is converted into a cube with the same volume. What is its edge length?
  2. OK circle
    circles2 Calculate the radius (circumradius) of the circle described right triangle with hypotenuse long 8 and one cathetus long 4.
  3. Invitations
    envelope For every 5 minutes writes Dana 10 invitations, while Anna 14 invitations. How long will write together 120 invitations?
  4. Permill
    permille How many permill is 1931 from 166456?
  5. Tunnels
    Mysky Mice had built an underground house consisting of chambers and tunnels: • each tunnel leading from the chamber to the chamber (none is blind) • from each chamber lead just three tunnels into three distinct chambers, • from each chamber mice can get to any
  6. Pool
    swimming-pool The swimming pool is 6 m wide and 14 m long and 185 cm deep. How many hectoliters of water is in it, if the water is 9 cm below its upper edge.
  7. Compare II
    powers Which of the numbers 158, 815 is greater?
  8. Shooter
    terc The probability that a good shooter hits the center of the target circle I is 0.22. The probability that the target hit intercircle is II 0.41. What is the probability that it hits the target circle I or II?
  9. Madams
    womans During the spring cleaning ladies going to wash windows. Mother takes wash all the windows 5 hours, the grandmother 3 times longer and Paula wash all windows in 5 hours. How many hours will spend washing the windows this "women's team" if working togethe
  10. ABS
    sphere_nice What is the value of ? ?
  11. Area codes
    us_codes How many 6 digit area codes are possible if the first number can't be zero?
  12. Teams
    football_team How many ways can divide 12 players into two teams of 6 member?
  13. Circle chord
    circleChord What is the length d of the chord circle of diameter 58 mm, if distance from the center circle is 24 mm?
  14. Angles and sides of the triangle
    trig Triangle ABC has a circumference of 26 cm. Lengths of the sides are as follows: a = 11.2 cm; b = 6.5 cm. Arrange the interior angles in order of its size. ?
  15. Radius
    green_circle Determine the radius of the circle, if its perimeter and area is the same number.
  16. 2nd class variations
    cards From how many elements you can create 6480 variations of the second class?
  17. Gauss
    kfgauss Help little C.F. Gauss sum all the integers from 1 to 340.
  18. 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.
  19. 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?
  20. 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?

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