Combinatorial number - problems

  1. A book
    books_32 A book contains 524 pages. If it is known that a person will select any one page between the pages numbered 125 and 384, find the probability of choosing the page numbered 252 or 253.
  2. Peaches
    broskve There are 20 peaches in the pocket. 3 peaches are rotten. What is the probability that one of the randomly picked two peaches will be just one rotten?
  3. Sweater
    colours_3 Dana confuses sweater and wool has a choice of seven colors. In how many ways she can choose from three colors to the sleeves?
  4. Word
    words What is the probability that a random word composed of chars H, T, M, A will be MATH?
  5. Chocolates
    Chocolate In the market have 4 kinds of chocolates. How many ways can we buy 23 chocolates?
  6. Rectangles
    rectangles How many rectangles with area 3002 cm2 whose sides is natural numbers are?
  7. Sales
    tesco From statistics of sales goods, item A buy 51% of people and item B buys 59% of people. What is the probability that from 10 people buy 2 item A and 8 item B?
  8. Candy
    bulls How many ways can divide 16 identical candies to 4 children?
  9. Stacks
    euro_stacks Annie has a total of $ 702. The money must be divided into stacks so that each buyer has the same amounth of dollars. How many options she have?
  10. N-gon
    ngon How many diagonals has convex 14-gon?
  11. Pairs
    dvojice From the five girls and four boys teachers have to choose one pair of boy and girl. A) How many such pairs of (M + F)? B) How many pairs where only boys (M + M)? C) How many are all possible pairs?
  12. Party
    party-informatikov At party overyone clink with everyone. Together, they clink 171 times. How many people were at the party?
  13. 2nd class combinations
    color_circle From how many elements you can create 4560 combinations of the second class?
  14. Lines
    lines_1 In how many points will intersect 14 different lines, where no two are parallel?
  15. Commitee
    committees A class consists of 6 males and 7 females. How many committees of 7 are possible if the committee must consist of 2 males and 5 females?
  16. Family
    stork_bocian What is the probability that a family with 7 childrens have: exactly 5 girls? 7 girls and 0 boys? Consider the birth probability of a girl is 48.69% and boy 51.31%.
  17. Bulbs
    bulb The probability that the bulb can operate 5000 hours is 0.16. What is the probability that exactly one of three bulbs can operate 5000 hours?
  18. Examination
    examination The class is 21 students. How many ways can choose two to examination?
  19. Math logic
    children_7 There are 20 children in the group, each two children have a different name. Alena and John are among them. How many ways can we choose 8 children to be among the selected A) was John B) was John and Alena C) at least one was Alena, John D) maximum one w
  20. Tournament
    turnaj Determine how many ways can be chosen two representatives from 34 students to school tournament.

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