Reason - 9th grade (14y) - math problems

Number of problems found: 474

  • Tricolors
    Flag_of_the_Netherlands.svg From the colors - red, blue, green, black and white, create all possible tricolors.
  • Two-element combinations
    combinatorics Write all two-element combinations from elements a, b, c, d.
  • Six on dice
    dices2_1 What is the probability that when throwing two dice will fall at least one six?
  • Probability
    fractions_1 How probable is a randomly selected three-digit number divisible by five or seven?
  • Chess
    chess How many different ways can initiate a game of chess (first pass)?
  • Diofant equation
    eq222_19 250x + 120y = 5640
  • One three
    dice We throw two dice. What is the probability that max one three falls?
  • Lines
    lines_1 In how many points will intersect 14 different lines, where no two are parallel?
  • Subsets
    venn5 How many 19 element's subsets can be made from the 26 element set?
  • Algebrogram
    plus_2 Solve algebrogram: mama+anna=vari How many solutions are?
  • Consecutive numbers
    progression Sum of ten consecutive numbers is 105. Determine these numbers (write first and last).
  • Bookshelf and books
    bookshelf How many ways can we place 7 books in a bookshelf?
  • The dice
    hracia-kocka What is the probability of events that if we throw a dice is rolled less than 6?
  • Coins
    mince_1 On coins found was stated that from the year 87 BC. It is right?
  • Dice
    dices How many times must throw the dice, the probability of throwing at least one six was greater than 90%?
  • Seating
    kupe_1 How many ways can 6 people sit on 6 numbered chairs (e. g. , seat reservation on the train)?
  • Three-digit
    seven How many do three-digit natural numbers not have the number 7?
  • Progression
    sequence_geo_10 -12, 60, -300,1500 need next 2 numbers of pattern
  • Right
    r_triangle_1 Determine angles of the right triangle with the hypotenuse c and legs a, b, if: ?
  • Hexagon = 8 parts
    stef.6.11.99 Divide the regular hexagon into eight equal parts.

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Reason - math problems. Examples for 9th grade.