Combinatorics - examples

Would you like to compute count of combinations?

  1. Six on dice
    dices2_1 What is the probability that when throwing two dice will fall at least one six?
  2. Sum on dice
    dices2 We have two dice. What is the greater likelihood of fall a total sum 7 or 8 ? (write 7, 8 or 0 if the probabilities are the same)?
  3. Sum or product
    dice_6 What is the probability that two dice fall will have the sum 7 or product 12?
  4. Lines
    lines_4 How many lines can be draw with 8 points, if three points lie on one line and the other any three points do not lie on the same line?
  5. Three-digit
    seven How many three-digit natural numbers do not have the number 7?
  6. Digits
    numbers_48 How many five-digit numbers can be written from numbers 0.3,4, 5, 7 that is divided by 10 and if digits can be repeated.
  7. Doctor 2
    heart A doctor noted the Diastolic Blood Pressure (DBP) of a large number of patients. Later, he scrambled the data to keep the privacy of his patients. Based on the scrambled dataset, he finds that the lower inner fence is equal to 50 and the upper inner fenc
  8. Rectangle
    diagonal In rectangle with sides 10 and 9 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?
  9. 7 heroes
    7statocnych 5 heroes galloping on 5 horses behind. How many ways can sort them behind?
  10. No. of divisors
    triangle_div How many different divisors has number ??
  11. Flags
    vlajka_cz How many different flags can be made from colors red, white, blue, black, yellow, green, purple, gray, orange so that each flag consisted of three different colors?
  12. Vans
    shuttlevan In how many ways can 7 shuttle vans line up at the airport?
  13. Ace
    ace From complete sets of playing cards (32 cards) we pulled out one card. What is the probability of pulling the ace?
  14. Seating
    kupe_1 How many ways can 7 people sit on 3 numbered chairs (eg seat reservation on the train)?
  15. Pediatrician
    doctor Pediatrician this month of 21 working days takes 3 days holidays. What is the probability that on Monday will be at work?
  16. 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
  17. Guests
    hostia How many ways can 7 guests sit down on 9 seats standing in a row?
  18. 2nd class variations
    cards From how many elements you can create 6480 variations of the second class?
  19. Word
    words What is the probability that a random word composed of chars T, I, O, D, I will be IDIOT?
  20. Shelf
    bookshelf.JPG How many ways are there to arrange 9 books on a shelf?

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