Probability + percentages - 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.

Number of problems found: 50

  • 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 (chance is the same)?
  • Events
    items Event P has probability of 0.84. What is the probability that the event P occurs in 3, 5, 7 try.
  • Shooter
    terc The probability that a good shooter hits the center of the target circle I is 0.1. The probability that the target hit intercircle is II 0.58. What is the probability that it hits the target circle I or II?
  • Two doctors
    dr_cvach Doctor A will determine the correct diagnosis with a probability of 93% and doctor B with a probability of 79%. Calculate the probability of proper diagnosis if both doctors diagnose the patient.
  • 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?
  • 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%.
  • Probability - tickets
    zreby What is the probability when you have 25 tickets in 5000 that you not wins the first (one) prize?
  • Probability
    fractions_1 How probable is a randomly selected three-digit number divisible by five or seven?
  • Utopia Island
    doktori A probability of disease A on the island of Utopia is 40%. A probability of occurrence among the men of this island, which make up 60% of all the population (the rest are women), is 50%. What is the probability of occurrence of A disease among women on Ut
  • Three dice
    dices_5 What is the probability that when we roll three dice, we roll the numbers 1,2,3?
  • Ace or king
    cards What is the probability that we will choose an ace or a king when choosing from a deck of sevens cards?
  • Three reds
    sedma What is the probability that when choosing 3 carats from seven carats, all 3 reds will be red?
  • Sum 10
    dices11 What is the probability that two dice throw twice in a row will result the sum of 10?
  • 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?
  • Win in raffle
    tombola_1 The raffle tickets were sold 200, 5 of which were winning. What is the probability that Peter, who bought one ticket will win?
  • Three colors
    balls2 Find the probability that 3 balls of the same color will be drawn from fate with 10 white, 10 red, and 10 blue balls.
  • Family
    family_32 94 boys are born per 100 girls. Determine the probability that there are two boys in a randomly selected family with three children.
  • Ace
    ace From complete sets of playing cards (32 cards), we pulled out one card. What is the probability of pulling the ace?
  • Two aces
    cards_7 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?
  • Throw
    dices6_1 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?

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