Variations - examples

  1. Boys and girls
    boy_6 There are eight boys and nine girls in the class. There were six children on the trip from this class. What is the probability that left a) only boys b) just two boys
  2. Inverted nine
    In the hotel,, Inverted nine" each hotel room number is divisible by 6. How many rooms we can count with three-digit number registered by digits 1,8,7,4,9?
  3. No. of divisors
    triangle_div How many different divisors has number ??
  4. 7 heroes
    7statocnych 9 heroes galloping on 9 horses behind. How many ways can sort them behind?
  5. Flags
    vlajka_cz How many different flags can be made from colors purple, yellow, red, white, blue, green, orange so that each flag consisted of three different colors?
  6. Vans
    shuttlevan In how many ways can 7 shuttle vans line up at the airport?
  7. Seating
    kupe_1 How many ways can 10 people sit on 0 numbered chairs (eg seat reservation on the train)?
  8. Guests
    hostia How many ways can 5 guests sit down on 6 seats standing in a row?
  9. 2nd class variations
    cards From how many elements you can create 6972 variations of the second class?
  10. Football league
    football In the 5th football league is 10 teams. How many ways can be filled first, second and third place?
  11. Pairs
    pair At the table sit 8 people, 4 on one side and 4 on the other side. Among them are 3 pairs. Every pair wants to sit opposite each other. How many ways can they sit?
  12. Morse alphabet
    morse_code Calculate how many words of Morse code to create compiling commas and dots in the words of one to four characters.
  13. Coin and die
    die Flip a coin and then roll a six-sided die. How many possible combinations are there?
  14. Lock
    combination-lock Combination lock will open when the right choice of 3 numbers (from 1 to 25 inclusive) is selected. A. How many different lock combinations are possible? B. Is he combination lock named appropriately?
  15. N-gon
    ngon How many diagonals has convex 11-gon?
  16. Bits, bytes
    bits Calculate how many different numbers can be encoded in 16-bit binary word?
  17. Subsets
    1venna_sets How many are all subsets of set ??
  18. Area codes
    us_codes How many 6 digit area codes are possible if the first number can't be zero?
  19. Hockey players
    players After we cycle five hockey players sit down. What is the probability that the two best scorers of this crew will sit next to each other?
  20. Numbers
    numbers_3 How many different 7 digit natural numbers in which no digit is repeated, can be composed from digits 0,1,2,3,4,5,6?

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