Probability - high school - math problems

Probability is the measure of the likeliness that an event will occur. The probability (chance) is a value from the interval <0;1> or in percentage (0% to 100%) expressing the occurrence of some event. 0 is impossible event and 1 (100%) means the certainty event.

  1. Rectangle
    diagonal In rectangle with sides, 6 and 3 mark the diagonal. What is the probability that a randomly selected point within the rectangle is closer to the diagonal than to any side of the rectangle?
  2. Ace
    ace From complete sets of playing cards (32 cards), we pulled out one card. What is the probability of pulling the ace?
  3. 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?
  4. 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.
  5. Dice
    dices How many times must throw the dice, the probability of throwing at least one six was greater than 90%?
  6. Scrap
    chair_bad From 6 products are 3 scrap. What is the probability that the random pick of 2 products have no defective product?
  7. Sales
    tesco From statistics of sales goods, item A buy 51% of people and item B buys 59% of people. What is the probability that from 10 people buy 2 item A and 8 item B?
  8. Dices
    dices_2 We will throw two dice. What is the probability that the ratio between numbers on first and second dice will be 1:2?
  9. Event probability
    dices_1 The probability of event P in 8 independent experiments is 0.33. What is the probability that the event P occurs in one experiment (probability is same)?
  10. 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?
  11. Events
    items Event P has probability of 0.84. What is the probability that the event P occurs in 3, 5, 7 try.
  12. 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?
  13. Hockey players
    players After we cycle five hockey players sit down. What is the probability that the two best scorers of this crew will sit next to each other?
  14. Lottery
    loteria_1 The lottery is 60000 elk in which 6200 wins. What is the probability that the purchase of 12 elks won nothing?
  15. 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. W
  16. Family
    stork_bocian What is the probability that a family with 7 childrens have: exactly 5 girls? 7 girls and 0 boys? Consider the birth probability of a girl is 48.69% and boy 51.31%.
  17. 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?
  18. Bulbs
    bulb The probability that the bulb can operate 4000 hours is 0.3. What is the probability that exactly one of eight bulbs can operate 4000 hours?
  19. Raffle
    tombola How many raffle tickets must be purchased by Peter in raffle with issued 200 tickets if he wants to be sure win at least 3 price? In the raffle draws 30 prices.
  20. The dice
    hracia-kocka What is the probability of events that if we throw a dice is rolled less than 6?

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