# Permutations - problems

1. 7 heroes
9 heroes galloping on 9 horses behind. How many ways can sort them behind?
2. 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?
3. Vans
In how many ways can 9 shuttle vans line up at the airport?
4. Seating
How many ways can 7 people sit on 3 numbered chairs (eg seat reservation on the train)?
5. Word
What is the probability that a random word composed of chars T, H, A, M will be MATH?
6. Shelf
How many ways are there to arrange 6 books on a shelf?
7. Phone numbers
How many 7-digit telephone numbers can be compiled from the digits 0,1,2,..,8,9 that no digit is repeated?
8. Rectangles
How many rectangles with area 3032 cm2 whose sides is natural numbers are?
9. Playing cards
How many possible ways are to shuffle 7 playing cards?
10. Pairs
At the table sit 8 people, 4 on one side and 4 on the other side. Among them are 3 pairs. Every pair wants to sit opposite each other. How many ways can they sit?
11. Lock
Combination lock will open when the right choice of 5 numbers (from 1 to 12 inclusive) is selected. A. How many different lock combinations are possible? B. Is he combination lock named appropriately?
12. N-gon
How many diagonals has convex 11-gon?
13. Subsets
How many are all subsets of set ??
14. Kids
How many different ways can sit 8 boys and 3 girls in line, if girls want to sit on the edge?
15. Hockey 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?
16. Numbers
How many different 7 digit natural numbers in which no digit is repeated, can be composed from digits 0,1,2,3,4,5,6?
17. School trip
Class has 17 students. What different ways students can be accommodated in the hostel, where available 3× 2-bed, 1× 3-bed and 2× 4-bed rooms. (Each room has its own unique number)
18. Toys
3 children pulled 12 different toys from a box. Many ways can be divided toys so that each children had at least one toy?
19. Chess
How many ways can select 4 fields on classic chess board with 64 fields, so that fields don't has the same color?