Combinatorial number - math problems

Number of problems found: 136

  • Combinations
    kvadrat 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?
  • Count of triangles
    SquareTriangle Given a square ABCD and on each side 8 internal points. Determine the number of triangles with vertices at these points.
  • Trinity
    trojka How many different triads can be selected from group 38 students?
  • Diagonals
    diagonals What x-gon has 54 diagonals?
  • N-gon
    ngon How many diagonals has convex 11-gon?
  • Hockey
    hokej The hockey match ended 8:2. How many different matches could be?
  • Combinations
    math From how many elements we can create 990 combinations 2nd class without repeating?
  • Examination
    examination The class is 21 students. How many ways can choose two to examination?
  • Teams
    football_team How many ways can divide 16 players into two teams of 8 member?
  • Research in school
    numbers For particular research in high school, four pupils are to be selected from a class with 30 pupils. Calculate the number of all possible results of the select and further calculate the number of all possible results, if it depends on the order in which th
  • A pizza
    pizza A pizza place offers 14 different toppings. How many different three topping pizzas can you order?
  • Combinations
    trezor How many elements can form six times more combinations fourth class than combination of the second class?
  • 2nd class combinations
    color_circle From how many elements you can create 4560 combinations of the second class?
  • Menu
    jedalnicek On the menu are 12 kinds of meal. How many ways can we choose four different meals into the daily menu?
  • Disco
    vencek On the disco goes 12 boys and 15 girls. In how many ways can we select four dancing couples?
  • Dice
    dices2 We throw five times the dice. What is the probability that six fits exactly twice?
  • Committees
    globe How many different committees of 2 people can be formed from a class of 21 students?
  • Combinatorics
    fontains The city has 7 fountains. Works only 6. How many options are there that can squirt ?
  • Two-element combinations
    combinatorics Write all two-element combinations from elements a, b, c, d.
  • Dice
    dices2 We throw 10 times a playing dice. What is the probability that the six will fall exactly 4 times?

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