Combinatorics - math word problems

  1. Hearts
    hearts_cards 5 cards are chosen from a standard deck of 52 playing cards (13 hearts) with replacement. What is the probability of choosing 5 hearts in a row?
  2. Events
    items Event P has probability of 0.84. What is the probability that the event P occurs in 3, 5, 7 try.
  3. Pizza
    pizza_1 A school survey found that 12 out of 15 students like pizza. If 6 students are chosen at random, what is the probability that all 6 students like pizza?
  4. 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?
  5. Pediatrician
    doctor Pediatrician this month of 20 working days takes 8 days holidays. What is the probability that on Monday will be at work?
  6. TV fail
    old_tv The TV has after 10,000 hours average 25 failures. Determine the probability of TV failure after 200 hours of operation.
  7. Lines
    lines_1 In how many points will intersect 14 different lines, where no two are parallel?
  8. 7 heroes
    7statocnych 9 heroes galloping on 9 horses behind. How many ways can sort them behind?
  9. Raffle
    tombola_tickets In the pool is numbers from 1 to 115. What is the probability that a randomly selected number is not a prime number?
  10. Hockey
    hokej Hockey match ended 8:2. How many different matches could be?
  11. 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?
  12. Calculation of CN
    color_combinations Calculate: ?
  13. 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 th
  14. Subsets
    1venna_sets How many are all subsets of set ??
  15. Bulbs
    bulbs In the box are 6 bulbs with power 75 W, 14 bulbs with power 40 W and 15 with 60 W. Calculate probability that a randomly selected bulb is:
  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. Rectangles
    rectangles How many rectangles with area 8713 cm2 whose sides is natural numbers are?
  18. Shooters
    soldiers In army regiment are six shooters. The first shooter target hit with a probability of 49%, next with 75%, 41%, 20%, 34%, 63%. Calculate the probability of target hit when shooting all at once.
  19. 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?
  20. 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)?

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