Combinatorics - examples

  1. Combinations 7
    combinatorics A multi-course meal has 3 choices. 3 appetizers, 4 main courses, and 3 desserts. How many different combinations to choose from?
  2. How many 2
    chart_2 How many three lettered words can be formed from letters A B C D E G H if repeats are: a) not allowed b) allowed
  3. Left handed
    pens_1 It is known that 25% of the population is left-handed. What is the probability that there is a maximum of three left-handers at a seminar where there are 30 participants?
  4. Component fail
    matica There is a 90 percent chance that a particular type of component will perform adequately under high temperature conditions. If the device involved has four such components, determine the probability that the device is inoperable because exactly one of the.
  5. Prime number
    prime_2 Jan wrote any number from 1 to 20. What is the probability that he wrote the prime number?
  6. No. of divisors
    triangle_div How many different divisors has number ??
  7. Rectangle
    diagonal In rectangle with sides 3 and 10 mark the diagonal. What is the probability that a randomly selected point within the rectangle is closer to the diagonal than to any side of the rectangle?
  8. 7 heroes
    7statocnych 9 heroes galloping on 9 horses behind. How many ways can sort them behind?
  9. Ace
    ace From complete sets of playing cards (32 cards) we pulled out one card. What is the probability of pulling the ace?
  10. 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?
  11. Vans
    shuttlevan In how many ways can 7 shuttle vans line up at the airport?
  12. Seating
    kupe_1 How many ways can 9 people sit on 3 numbered chairs (eg seat reservation on the train)?
  13. Pediatrician
    doctor Pediatrician this month of 21 working days takes 3 days holidays. What is the probability that on Monday will be at work?
  14. Guests
    hostia How many ways can 5 guests sit down on 6 seats standing in a row?
  15. Bureau of Labor
    UPSVAR Bureau of Labor is a state institution that provides mike and the rest for their so-called clients. The mission of the Bureau of Labor is spend taxpayer money to provide relaxation and benefits to those who do not want to work. Popularly speaking sense the
  16. 2nd class variations
    cards From how many elements you can create 6972 variations of the second class?
  17. Word
    words What is the probability that a random word composed of chars T, H, A, M will be MATH?
  18. Shelf
    bookshelf.JPG How many ways are there to arrange 6 books on a shelf?
  19. Chocolates
    Chocolate In the market have 4 kinds of chocolates. How many ways can we buy 19 chocolates?
  20. 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?

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