Combinatorics - examples - page 10

  1. Combinations
    kvadrat_3 If the number of elements increase by 3, it increases the number of combinations of the second class of these elements 5 times. How many are the elements?
    math_1 How many words can be created from the word MATEMATIKA by changing the order of the letters, regardless of whether or not the words are meaningful?
  3. Points in plane
    linear_eq_1 The plane is given 12 points, 5 of which is located on a straight line. How many different lines could by draw from this points?
  4. Elements
    fact_1 If the number of elements is decreased by two the number of permutations is decreased 30 times. How many elements are?
  5. Seagull
    cajka Artificially created island in the shape of a circle with a radius of 50 m is overgrown with grass. The only exception is a landing area for helicopters in the shape of a rectangle measuring 15 m and 8 m. What is the probability that the flying seagull (wi
  6. Variation equation
    fun2_4 Solve combinatorics equation: V(2, x+8)=72
  7. Combinations
    trezor_1 How many elements can form six times more combinations fourth class than combination of the second class?
  8. Box and whisker plot
    box-whisker-plot Construct a box and whisker plot for the given data. 56, 32, 54, 32, 23, 67, 23, 45, 12, 32, 34, 24, 36, 47, 19, 43
  9. Dice
    dices2_4 We throw five times the dice. What is the probability that six fits exactly twice?
  10. Boys and girls
    boy_6 There are eight boys and nine girls in the class. There were six children on the trip from this class. What is the probability that left a) only boys b) just two boys
  11. Dice
    dices2_5 We throw 10 times a play dice, what is the probability that the six will fall exactly 4 times?
  12. Triangles
    triangle_234_1 Five sticks with a length of 2,3,4,5,6 cm. How many ways can you choose three sticks to form three sides of a triangle?
  13. Page numbering
    books_10 The book has 88 pages. How many times is the number 4 used for the book numbering?
  14. Families 2
    family_24 There are 729 families having 6 children each. The probability of a girl is 1/3 and the probability of a boy is 2/3. Find the the number of families having 2 girls and 4 boys.
  15. Test
    test_4 The teacher prepared a test with ten questions. The student has the option to choose one correct answer from the four (A, B, C, D). The student did not get a written exam at all. What is the probability that: a) He answers half correctly. b) He answers.
  16. Raffle
    tombola_3 There are 200 draws in the raffle, but only 20 of them win. What is the probability of at least 4 winnings for a group of people who have bought 5 tickets together?
  17. Left handed
    pens_1 It is known that 25% of the population is left-handed. What is the probability that there is a maximum of three left-handers at a seminar where there are 30 participants?
  18. Three students
    terc2_2 Three students independently try to solve the problem. The first student will solve a similar problem with a probability of 0.6, the second student will solve at a probability of 0.55, and the third will solve at a probability 0.04. The problem is resolved
  19. Seven
    post_1 Seven friends agree to send everyone a holiday card. How many postcards were sent?
  20. Utopia Island
    doktori A probability of disease A on the island of Utopia is 40%. A probability of occurrence among the men of this island, which make up 60% of all the population (the rest are women), is 50%. What is the probability of occurrence of A disease among women on Uto

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