Combinatorics - math word problems

  1. Balls
    gulky From the bag with numbered balls (numbers 1,2,3,. ..20) we pick one ball. What is the probability of choosing a number containing 1?
  2. Graduation party
    dancers There are 15 boys and 12 girls at the graduation party. Determine how many four couples can be selected.
  3. Records
    binomial_1 Records indicate 90% error-free. If 8 records are randomly selected, what is the probability that at least 2 records have no errors?
  4. Genetic disease
    flu One genetic disease was tested positive in both parents of one family. It has been known that any child in this family has a 25% risk of inheriting the disease. A family has 3 children. What is the probability of this family having one child who inherited.
  5. Dice and coin
    dice A number cube is rolled and a coin is tossed. The number cube and the coin are fair. What is the probability that the number rolled is greater than 2 and the coin toss is head?
  6. Rectangle
    diagonal In rectangle with sides, 6 and 3 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?
  7. No. of divisors
    triangle_div How many different divisors has number ??
  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 white, red, green, purple, orange, yellow, blue so that each flag consisted of three different colors?
  11. Vans
    shuttlevan In how many ways can 9 shuttle vans line up at the airport?
  12. Seating
    kupe_1 How many ways can 5 people sit on 4 numbered chairs (e. G. , seat reservation on the train)?
  13. Pediatrician
    doctor Pediatrician this month of 20 working days takes 4 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. Word
    words What is the probability that a random word composed of chars E, Y, G, E, R, O, M, T will be the GEOMETRY?
  17. 2nd class variations
    cards From how many elements you can create 2450 variations of the second class?
  18. Shelf
    bookshelf.JPG How many ways are there to arrange 6 books on a shelf?
  19. Orchard
    orchard 3 trees in 3 lines grows in the orchard. How many trees are in the orchard?
  20. Chocolates
    Chocolate In the market have 3 kinds of chocolates. How many ways can we buy 14 chocolates?

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