Multiplication principle - high school - math problems

  1. Recruitment
    numbers_1
  2. Birthday paradox
    holland How large must the group of people be so that the probability that two people have a birthday on the same day of the year is greater than 90%?
  3. The test
    test The test contains four questions, and there are five different answers to each of them, of which only one is correct, the others are incorrect. What is the probability that a student who does not know the answer to any question will guess the right answer
  4. Fall sum or same
    dices2 Find the probability that if you roll two dice, it will fall the sum of 10, or the same number will fall on both dice.
  5. Birth
    probability Let's assume that the probability of the birth of a boy and a girl in the family is the same. What is the probability that in a family with five children, the youngest and oldest child is a boy?
  6. The university
    family_1 At a certain university, 25% of students are in the business faculty. Of the students in the business faculty, 66% are males. However, only 52% of all students at the university are male. a. What is the probability that a student selected at random in t
  7. Divide
    hrusky How many different ways can three people divide 7 pears and 5 apples?
  8. Possible combinations - word
    dices2 How many ways can the letters F, A, I, R be arranged?
  9. Beads
    koralky2 How many ways can we thread 4 red, 5 blue, and 6 yellow beads onto a thread?
  10. Cube construction
    222cube A 2×2×2 cube is to be constructed using 4 white and 4 black unit cube. How many different cubes can be constructed in this way? ( Two cubes are not different if one can be obtained by rotating the other. )
  11. Boys and girls
    dancers There are 20 boys and 10 girls in the class. How many different dance pairs can we make of them?
  12. Two groups
    skola The group of 10 girls should be divided into two groups with at least 4 girls in each group. How many ways can this be done?
  13. Graduation party
    dancers There are 15 boys and 12 girls at the graduation party. Determine how many four couples can be selected.
  14. One three
    dice We throw two dice. What is the probability that max one three falls?
  15. Menu
    jedalnicek On the menu are 12 kinds of meal. How many ways can we choose four different meals into the daily menu?
  16. Bookshelf and books
    bookshelf How many ways can we place 7 books in a bookshelf?
  17. A jackpot
    jackpot3 How many times must I play this jackpot to win? A jackpot of seven games having (1 X 2), i. E. , home win or away win.
  18. Three-digit integers
    numbers2_49 How many three-digit natural numbers exist that do not contain zero and are divisible by five?
  19. Classroom
    ziaci_7 Of the 26 pupils in the classroom, 12 boys and 14 girls, four representatives are picked to the odds of being: a) all the girls b) three girls and one boy c) there will be at least two boys
  20. Three workplaces
    workers_49 How many ways can we divide nine workers into three workplaces if they need four workers in the first workplace, 3 in the second workplace and 2 in the third?

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