# 9th grade (14y) + multiplication principle - examples

1. One three We throw two dice. What is the probability that max one three falls?
2. No. of divisors How many different divisors has number ??
3. 7 heroes 9 heroes galloping on 9 horses behind. How many ways can sort them behind?
4. 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?
5. Vans In how many ways can 9 shuttle vans line up at the airport?
6. Seating How many ways can 6 people sit on 3 numbered chairs (e. G. , seat reservation on the train)?
7. Guests How many ways can 5 guests sit down on 6 seats standing in a row?
8. 2nd class variations From how many elements you can create 2450 variations of the second class?
9. Shelf How many ways are there to arrange 6 books on a shelf?
10. Phone numbers How many 7-digit telephone numbers can be compiled from the digits 0,1,2,..,8,9 that no digit is repeated?
11. Rectangles How many rectangles with area 3032 cm2 whose sides is natural numbers are?
12. Football league In the 5th football league is 10 teams. How many ways can be filled first, second and third place?
13. Playing cards How many possible ways are to shuffle 7 playing cards?
14. 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?
15. Morse alphabet Calculate how many words of Morse code to create compiling commas and dots in the words of one to four characters.
16. Coin and die Flip a coin and then roll a six-sided die. How many possible combinations are there?
17. 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?
18. Subsets How many are all subsets of set ??
19. 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?
20. Bits, bytes Calculate how many different numbers can be encoded in 16-bit binary word?

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