Combinatorial number - math problems

Number of problems found: 139

  • Binomial probability
    binomial What is the binominal probability that at least 4 of the 6 trials (n=6) are succeeded where φ = 0.50?
  • C(6,3)
    combinatorics C(6,3) + 3 P(6,3)
  • Committee 2
    workers How many committee consisting of 3 women and 2 men can be formed from a group of 6 woman and 5 men?
  • There 8
    dices2 There are 7 women and 5 men in a department. a) how many ways can a committee of 3 people be selected? b) how many ways can a committee of 2 men and 1 woman be selected? c) how many ways can a committee of at least 2 woman be selected (3 people total)?
  • Created trio
    skola What is the probability that in the created trio, which consists of 19 boys and 12 girls, they will be: a) the boys themselves b) the girls themselves c) 2 boys and 1 girl?
  • Bernoulli distribution
    binomial The production of solar cells produces 2% of defective cells. Assume the cells are independent and that a lot contains 800 cells. Approximate the probability that less than 20 cells are defective. (Answer to the nearest 3 decimals).
  • The six
    lanovka The six boys are to be led up the hill by a two-seater lift. How many options are there?
  • Covid-19
    flu Data showed that 22% of people in a small town was infected with the COVID-19 virus. A random sample of six residents from this town was selected. Find the probability that exactly two of these residents was infected.
  • Doctors
    doktori The drug successfully treats 90% of cases. Calculate the probability that he will cure at least 18 patients out of 20?
  • Seeds
    mrkva2 The germination of seeds of a certain species of carrot is 96%. What is the probability that at least 25 seeds out of 30 will germinate?
  • Wimbledon finals
    tenis Serena Williams made a successful first serve 67% 0f the time in a Wimbledon finals match against her sister Venus. If she continues to serve at the same rate the next time they play and serves 6 times in the first game, determine the probability that: 1.
  • Seedbeds
    mrkva2 The father wants to plant 2 seedbeds of carrot and 2 seedbeds of onion. Use a tree chart to find how many different options for placing the seedbeds he has.
  • Honored students
    metals Of the 25 students in the class, 10 are honored. How many ways can we choose 5 students from them, if there are to be exactly two honors between them?
  • A license
    License_Plate A license plate has
3 letters followed by 4 numbers. Repeats are not allowed for the letters, but they are for the numbers. If they are issued at random, what is the probability that the 3 letters are in alphabetical order and the 3 numbers are consecutiv
  • School parliament
    slovakia There are 18 boys and 14 girls in the class. In how many ways can 3 representatives be elected to the school parliament, if these are to be: a) the boys themselves b) one boy and two girls
  • Two-element combinations
    combinatorics Write all two-element combinations from elements a, b, c, d.
  • Soccer teams
    lopticky Have to organize soccer teams. There are 3 age groups. How many different ways can you organize teams of ten for each age group? Is this a permutation or combination?
  • Alopecia
    alopecia Medical literature indicates that 45% of men suffer from alopecia. For random sample of 8 men, calculate the probability that: (a) exactly four men suffer from alopecia. (b) at most two men suffer from alopecia.
  • Ten persons
    TUCWGKGHCVGBPEMEP75TVAR5LA Ten persons, each person makes a hand to each person. How many hands were given?
  • Playing cards
    binomial From 32 playing cards containing 8 red cards, we choose 4 cards. What is the probability that just 2 will be red?

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