Combinatorics - examples - page 2

  1. Rectangles
    rectangles How many rectangles with area 3002 cm2 whose sides is natural numbers are?
  2. Football league
    football In the 5th football league is 10 teams. How many ways can be filled first, second and third place?
  3. Dice
    dices How many times must throw the dice, the probability of throwing at least one six was greater than 90%?
  4. Playing cards
    playing_cards How many possible ways are to shuffle 7 playing cards?
  5. Candy
    bulls How many ways can divide 16 identical candies to 4 children?
  6. 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?
  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. 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.
  9. Scrap
    chair_bad From 6 products are 3 scrap. What is the probability that the random pick of 2 products have no defective product?
  10. 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?
  11. Coin and die
    die Flip a coin and then roll a six-sided die. How many possible combinations are there?
  12. 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?
  13. N-gon
    ngon How many diagonals has convex 11-gon?
  14. Dices
    dices_2 We will throw two dice. What is the probability that the ratio between numbers on first and second dice will be 1:2?
  15. Event probability
    dices_1 The probability of event P in 8 independent experiments is 0.33. What is the probability that the event P occurs in one experiment (probability is same)?
  16. Shooter
    terc The probability that a good shooter hits the center of the target circle I is 0.1. The probability that the target hit intercircle is II 0.58. What is the probability that it hits the target circle I or II?
  17. Events
    items Event N has probability of 0.24. What is the probability that the event N occurs in 8, 5, 4 try.
  18. 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?
  19. Balls
    spheres From the urn in which are 7 white balls and 17 red, gradually drag 3-times without replacement. What is the probability that pulls balls are in order: red red red?
  20. Bits, bytes
    bits Calculate how many different numbers can be encoded in 16-bit binary word?

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