Reason + multiplication principle - math problems

Number of problems found: 89

  • Math logic
    There are 20 children in the group, each two children have a different name. Alena and John are among them. How many ways can we choose 8 children to be among the selected A) was John B) was John and Alena C) at least one was Alena, John D) maximum one wa
  • First class
    The shipment contains 40 items. 36 are first grade, 4 are defective. How many ways can select 5 items, so that it is no more than one defective?
  • Two aces
    From a 32 card box we randomly pick 1 card and then 2 more cards. What is the probability that last two drawn cards are aces?
  • Salami
    How many ways can we choose 5 pcs of salami if we have 6 types of salami for 10 pieces and one type for 4 pieces?
  • Points in plane
    The plane is given 12 points, 5 of which are located on a straight line. How many different lines could be drawn from these points?
  • Four swords
    Obelix has three helmets, four swords, and five shields. How many words must make at the blacksmith forge Metallurgix to be able to walk another 90 days in unique armor?
  • Permutations
    How many 4-digit numbers can be composed of numbers 1,2,3,4,5,6,7 if: and the digits must not be repeated in the number b, the number should be divisible by five, and the numbers must not be repeated c, digits can be repeated
  • Competition
    15 boys and 10 girls are in the class. On school competition of them is selected 6-member team composed of 4 boys and 2 girls. How many ways can we select students?
  • Combinations of sweaters
    I have 4 sweaters two are white, 1 red and 1 green. How many ways can this done?
  • Dices throws
    What is the probability that the two throws of the dice: a) Six falls even once b) Six will fall at least once
  • Throw
    We throw 2 times with 2 dices. What is the probability that the first roll will fall more than sum of 9 and the second throw have sum 3 or does not have the sum 4?
  • Hockey game
    In the hockey game was made six goals. Czech played against Finland. Czechs won 4:2. In what order to fall goals? How many game sequences were possible during the game?
  • Three-digit numbers
    How many three-digit numbers are from the numbers 0 2 4 6 8 (with/without repetition)?
  • Hockey match
    The hockey match ended with a result of 3:1. How many different storylines may have the match?
  • The confectionery
    The confectionery sold 5 kinds of ice cream. In how many ways can I buy 3 kinds if order of ice creams does not matter?
  • The camp
    At the end of the camp a 8 friends exchanged addresses. Any friend gave remaining 7 friends his card. How many addresses they exchanged?
  • Three digits number
    From the numbers 1, 2, 3, 4, 5 create three-digit numbers that digits not repeat and number is divisible by 2. How many numbers are there?
  • Three digits number
    How many are three-digit integers such that they no digit repeats?
  • Chess
    How many different ways can initiate a game of chess (first pass)?
  • Seven-segmet
    Lenka is amused that he punched a calculator (seven-segment display) numbers and used only digits 2 to 9. Some numbers have the property that their image in the axial or central symmetry was again give some number. Determine the maximum number of three-di

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Reason - math problems. Multiplication principle - math problems.