# Combinatorics - math word problems

1. Hearts 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?
2. Events Event P has probability of 0.84. What is the probability that the event P occurs in 3, 5, 7 try.
3. Pizza 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?
4. Sales 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?
5. Pediatrician Pediatrician this month of 20 working days takes 8 days holidays. What is the probability that on Monday will be at work?
6. TV fail The TV has after 10,000 hours average 25 failures. Determine the probability of TV failure after 200 hours of operation.
7. Lines In how many points will intersect 14 different lines, where no two are parallel?
8. 7 heroes 9 heroes galloping on 9 horses behind. How many ways can sort them behind?
9. Raffle In the pool is numbers from 1 to 115. What is the probability that a randomly selected number is not a prime number?
10. Hockey Hockey match ended 8:2. How many different matches could be?
11. Rectangle 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?
12. Calculation of CN Calculate: ?
13. Bureau of Labor Bureau of Labor is a state institution that provides mike and the rest for their so-called clients. The mission of the Bureau of Labor is spend taxpayer money to provide relaxation and benefits to those who do not want to work. Popularly speaking sense th
14. Subsets How many are all subsets of set ??
15. Bulbs In the box are 6 bulbs with power 75 W, 14 bulbs with power 40 W and 15 with 60 W. Calculate probability that a randomly selected bulb is:
16. Word What is the probability that a random word composed of chars E, Y, G, E, R, O, M, T will be the GEOMETRY?
17. Rectangles How many rectangles with area 8713 cm2 whose sides is natural numbers are?
18. Shooters In army regiment are six shooters. The first shooter target hit with a probability of 49%, next with 75%, 41%, 20%, 34%, 63%. Calculate the probability of target hit when shooting all at once.
19. Shooter 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?
20. Event probability 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)?

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