Combinatorics - examples

1. Lathe
95% of the components manufactured on the lathe comply with the standard, of which 80% of the components are first-class. How likely can we expect a manufactured part to be first class?
On the menu are 12 kinds of meal. How many ways can we choose four different meals into the daily menu?
3. Probability of intersection
Three students have a probability of 0.7,0.5 and 0.4 to graduated from university respectively. What is the probability that at least one of them will be graduated?
4. A jackpot
How many times must I play this jackpot to win? A jackpot of seven games having (1 X 2), i. E. , home win or away win.
5. Rectangle
In rectangle with sides 10 and 8 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?
6. No. of divisors
How many different divisors has number ??
7. 7 heroes
9 heroes galloping on 9 horses behind. How many ways can sort them behind?
8. Ace
From complete sets of playing cards (32 cards) we pulled out one card. What is the probability of pulling the ace?
9. Flags
How many different flags can be made from colors white, red, green, purple, orange, yellow, blue so that each flag consisted of three different colors?
10. Vans
In how many ways can 9 shuttle vans line up at the airport?
11. Seating
How many ways can 7 people sit on 3 numbered chairs (eg seat reservation on the train)?
12. Pediatrician
Pediatrician this month of 19 working days takes 3 days holidays. What is the probability that on Monday will be at work?
13. Guests
How many ways can 5 guests sit down on 6 seats standing in a row?
14. 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 the
15. Word
What is the probability that a random word composed of chars T, H, A, M will be MATH?
16. 2nd class variations
From how many elements you can create 6972 variations of the second class?
17. Shelf
How many ways are there to arrange 6 books on a shelf?
18. Chocolates
In the market have 4 kinds of chocolates. How many ways can we buy 19 chocolates?
19. Phone numbers
How many 7-digit telephone numbers can be compiled from the digits 0,1,2,..,8,9 that no digit is repeated?
20. Two doctors
Doctor A will determine the correct diagnosis with a probability 86% and doctor B with a probability 86%. Calculate probability of correct diagnosis if patient is diagnosed by both doctors.

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