Combinatorics - math problems

Number of problems found: 400

  • How many 13
    exponentialFexsDecay How many ways can X³ y⁴ z³ be written without an exponent?
  • A box
    balls2 A box contains 6 red balls, 5 blue, and 4 white balls. Find the probability of drawing a) red ball b) non-white ball.
  • 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?
  • ID tag
    numbers2 How many 3 digit ID tag can be made if: a) a digit cannot be used more than once b) the  1st digit must be 5 and repetition of the others are not permitted.
  • 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)?
  • Three wagons
    wagon I have 6 different people (A, B, C, D, E, F), which I have to place into 3 wagons, if it depends on who will board. How many options are there?
  • Tic-tac-toe
    piskvorky In how many ways could 9 participants of the school round of five-in-a-row win the first 3 places?
  • The dice
    dice Find the probability that a number divisible by two or three will fall when the dice are rolled.
  • A bag
    balls2 A bag contains 9 blue marbles and 1 green marble. What is the probability of drawing a blue marble followed by a green marble, without replacing the first marble before drawing the second marble.
  • Double six-six
    dices2 What is the probability, that a player in the games of ludo will throw a double 6 twice .
  • We roll
    dices2 We roll two dice A. - what is the probability that the sum of the falling numbers is at most 4 B. - is at least 10 C. - is divisible by 5?
  • Twenty
    lastovicka Twenty swallows sit on a 10 m long telephone cable. Assume that swallows are completely randomly distributed along the line. (a) What is the probability that more than three swallows sit on a randomly selected section of cable 1 m long? (b) What is the pr
  • Seeds
    seed From a box of spruce seeds with the germination of 80%, we randomly select 10 seeds and plant them. Find the median of the random variable: the number of germinating seeds.
  • 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?
  • Crimson Lynx
    ship Captain Emily has a ship, the H. M. S Crimson Lynx. The ship is five furlongs from the dread pirate Umaima and her merciless band of thieves. If her ship hasn't already been hit, Captain Emily has probability 3/5 of hitting the pirate ship. If her ship ha
  • Two dice
    dices2 We roll two dice. What is the probability that the sum of the falling numbers is greater than 3?
  • Permutations with repetitions
    numbers2 How many times the input of 1.2.2.3.3.3.4 can be permutated into 4 digits, 3 digits and 2 digits without repetition? Ex: 4 digits = 1223, 2213, 3122, 2313, 4321. . etc 3 digits = 122.212.213.432. . etc 2 digits = 12, 21, 31, 23 I have tried permutation fo
  • Exchange € 100
    penize Find out how many ways you can exchange € 100 if you have an unlimited number of 50, 20, 10 and 5 euro banknotes. Use a method other than listing all options systematically.
  • The box
    bulbs The box contains three light bulbs with a wattage of 40 W and two pieces of light bulbs with a wattage of 60 W. What is the probability of the event that two randomly selected light bulbs will both be 40 W?
  • Mastering
    test The student masters the subject matter for the exam in Czech to 98%, from Math to 86% and from Economics to 71%. What is the probability that he will fail from Math and from others will succeed?

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