Combinatorics - math problems

Number of problems found: 393

  • 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.
  • One dice
    dice Calculate the probability of one dice roll with the numbers 1, 2, 3, 4, 5, 6 on the walls. Write the results in a notebook in the shape of a fraction in the basic form: 2/3. a, The number 1 falls on the cube. b, The number 5 falls on the cube. c, An even
  • Roads
    mapa There are 4 roads from city A to city B. There are 5 roads from city B to city C. How many different routes can we come from city A to city C via city B?
  • Number 4
    numbers Kamila wrote all natural numbers from 1 to 400 inclusive. How many times did she write the number 4?
  • Two-element combinations
    combinatorics Write all two-element combinations from elements a, b, c, d.
  • Three colors
    balls2 Find the probability that 3 balls of the same color will be drawn from fate with 10 white, 10 red, and 10 blue balls.
  • Wedding guests
    svatba_hatalovi Fifteen wedding guests could not agree on who would stand in the wedding photo. The groom suggested that all possible sets of wedding guests be made in the photographs.
  • School committee
    permutations Seven students were elected to the school committee. In how many ways can become the President, Vice-President, Secretary, and Treasurer be selected?
  • 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?
  • Study results
    vysvedcenie There are 7 students in the class with excellent results, 6 praiseworthy, 5 good, 4 sufficient, and 3 insufficient students. What is the probability that it will be a good student when summoned?
  • Ace or king
    cards What is the probability that we will choose an ace or a king when choosing from a deck of sevens cards?
  • Drawing from a hat
    klobouk When drawing numbers from a hat from 1 to 35, we select random given numbers. What is the probability that the drawn numbers will be divisible by 8 and 2?
  • Screws
    mosadz The box contains 8 iron, 6 brass, and 4 titanium screws. What is the probability that the randomly selected screw will not be brass?
  • Big numbers
    numbers How many natural numbers less than 10 to the sixth can be written in numbers: a) 9.8.7 b) 9.8.0
  • You have
    sane You have 4 reindeer and you want to have 3 fly your sleigh. You always have your reindeer fly in a single-file line. How many different ways can you arrange your reindeer?
  • The box
    cukriky The box contains five chocolate, three fruit, and two menthol candies. We choose sweets at random from the box. What probability will we take out one chocolate, one fruit, and one menthol candy without a return?
  • How many 4
    numbers2 How many four-digit numbers that are divisible by ten can be created from the numbers 3, 5, 7, 8, 9, 0 such no digits repeats?
  • Coffe cups
    hrnceky We have 4 cups with 4 different patterns. How many possible combinations can we create from 4 cups?
  • Tournament
    futball_ball How many matches will be played in a football tournament in which there are two groups of 5 teams if one match is played in groups with each other and the group winners play a match for the overall winner of the tournament?

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