Combinatorics - math word problems

Number of problems found: 302

  • Chocolates
    Chocolate In the market have 3 kinds of chocolates. How many ways can we buy 14 chocolates?
  • Kids
    kids How many different ways can sit 8 boys and 3 girls in line, if girls want to sit on the edge?
  • Trinity
    trojka How many different triads can be selected from the group 43 students?
  • Chess
    sachovnica How many ways can select 4 fields on classic chess board with 64 fields, so that fields don't has the same color?
  • Elections
    gaspar_billboard In elections candidate 10 political parties. Calculate how many possible ways can the elections finish, if any two parties will not get the same number of votes.
  • Two doctors
    dr_cvach Doctor A will determine the correct diagnosis with a probability 93% and doctor B with a probability 79%. Calculate probability of correct diagnosis if patient is diagnosed by both doctors.
  • Pairs
    pair At the table sit 10 people, 5 on one side and 5 on the other side. Among them are 3 pairs. Every pair wants to sit opposite each other. How many ways can they sit?
  • 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.
  • Bits, bytes
    bits Calculate how many different numbers can be encoded in 16-bit binary word?
  • Chords
    chords How many 4-tones chords (chord = at the same time sounding different tones) is possible to play within 7 tones?
  • Insurance
    tornado The owner of the house is insured against natural disasters and pays 0.04% annually of the value of house 77 Eur. Calculate the value of the house. Calculate the probability of disaster, if you know that 48% of the insurance is to pay damages.
  • Calculation of CN
    color_combinations Calculate: ?
  • Components
    components In the box are 8 white, 4 blue and 2 red components. What is the probability that we pull one white, one blue and one red component without returning?
  • Confectionery
    cukrovinky The village markets have 5 kinds of sweets, one weighs 31 grams. How many different ways a customer can buy 1.519 kg sweets.
  • Hearts
    hearts_cards 5 cards are chosen from a standard deck of 52 playing cards (13 hearts) with replacement. What is the probability of choosing 5 hearts in a row?
  • Word
    words What is the probability that a random word composed of chars E, Y, G, E, R, O, M, T will be the GEOMETRY?
  • Pizza
    pizza_1 A school survey found that 12 out of 15 students like pizza. If 6 students are chosen at random, what is the probability that all 6 students like pizza?
  • Balls
    spheres From the urn in which are 7 white balls and 17 red, gradually drag 3-times without replacement. What is the probability that pulls balls are in order: red red red?
  • Monty Hall
    Monty_open_door Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, say No. 3, which has a goat. Wh
  • Lines
    lines_1 In how many points will intersect 14 different lines, where no two are parallel?

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