Sets - math problems

Number of problems found: 120

  • The vaccination
    covid19 The vaccination coverage of the population is 80%. Unvaccinated make up 60% of all infected. What percentage are unvaccinated more likely to be infected?
  • An aircraft
    venn_intersect An aircraft manufacturing company has submitted bids on two separate airline contracts, A and B. The company feels that it has a 70% chance of winning contract A and a 25% chance of winning contract B. Furthermore, it believes that winning contract A is i
  • And-or probabilities
    venn P(A ) = 0.53, P(B) = 0.15, and P(A n B ) = 0.18. Find P(A U B ). Round approximations to two decimal places.
  • A fifth
    cinema A fifth grade class sets up 418 chairs for a graduation ceremony. Each row has 22 chairs. How many rows of chairs does the class set up? Enter your answer in the box.
  • There 11
    venn There are 50 pupil in the class. Out of of this number,1/10 speak French only and 4/5 of the 10 remainder speak both French and English . If the rest speak English only find the number of students who speak only English?
  • Smoker male
    venn_intersect For a person selected randomly from a certain population, events A and B are defined as follows. A = event the person is male B = event the person is a smoker. For this particular population, it is found that P(A ) = 0.53, P(B) = 0.15, and P(A n B ) = 0.1
  • Three subjects
    venn In a class of 40 students, 18 passed mathematics, 19 passed accounts, 16 passed economics, 5 mathematics and accounts only, 6 mathematics only, 9 accounts only, 2 accounts and economics only, if each student offered at least one of the subjects. a) how ma
  • C(6,3)
    combinatorics C(6,3) + 3 P(6,3)
  • A swimmer-training
    vennov_3_swim A swimmer-training program has 26 students specializing in the butterfly stroke, 24 specializing in the breaststroke, and 29 specializing in the backstroke. Of these students, 5 students are specializing in all three strokes, 5 are specializing in only th
  • 25 pupils
    skola 25 pupils attend the school dance group, which is 5 percent of all pupils in the school. The judo class is attended by 20 pupils of the school, a quarter of whom also go to a dance group. How many schoolchildren do not go to a dance or judo group?
  • Gym center
    sale 80% of all visitors to the gym center enjoy a discount. 3/4 of all visitors go to practice regularly. All visitors who go to the gym regularly benefit from a discount. What percentage of all visitors do not go to the gym regularly but still use the discou
  • Coloured teacups
    venn The teacups in Tea Stop 55 are `2/5` green and `3/10` yellow. What fraction of the teacups are neither green nor yellow?
  • The collector
    film Harry liked to collect old movies. On 4 different days, he bought 2 movies. On 2 other days, he bought 3 movies each day. After that he sold 2 sets of 2 movies. He figured out how many he had total, and then he divided that total into 2 groups to put onto
  • They bought
    skola They bought the students a set of notebooks for 65 euros. The first set cost € 2 and the second € 3. There were 5 times as many two-euro sets as three-set ones. How many sets of workbooks are there?
  • In a 5
    futball_ball In a football game, Mike, gets to play be the goalkeeper 50% of the time if Peter is the coach. But if Robert is coaching, he only has 30% chance. Peter coaches more than Robert in about 6 to 10 games. What is the probability that Mike gets to be the goal
  • Group of children
    family There is a group of children. There is a boy named Adam in each of the three children subgroup and a girl named Beata in each quartet (four-member subgroup). How many children can be in such a group and what are their names in that case?
  • Open intervals
    intervals.svg Open intervals A = (x-2; 2x-1) and B = (3x-4; 4) are given. Find the largest real number for which A ⊂ B applies.
  • Operations with sets
    venn5 The set B - A has twice as fewer elements than the set A - B and four times fewer elements than the set A ∩ B. How many times more elements does the set A have than the set B?
  • MF graduate
    venn 78 school students graduate from mathematics or physics. There are three times more students who graduate from mathematics and do not graduate from physics than those who graduate from physics and do not graduate from mathematics. 69 students graduate fro
  • Subtracting sets
    venn_intersect For two sets K, L is true: K has 30 elements, L has 27 elements and the set L - K has 22 elements. How many elements does the set K - L have?

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