Combinatorics - problemsWould you like to compute count of combinations?
- No. of divisors
How many different divisors has number ??
From complete sets of playing cards (32 cards) we pulled out one card. What is the probability of pulling the ace?
3 children pulled 9 different toys from a box. Many ways can be divided toys so that each children had at least one toy?
The class is 22 students. How many ways can choose four to examination?
- 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?
If probabilities of A, B and A ∩ B are P (A) = 0.57 P (B) = 0.73 and P (A ∩ B) = 0.12 calculate the following probability (of union. intersect and opposite and its combinations):
- Three digits number 2
Find the number of all three-digit positive integers that can be put together from digits 1,2,3,4 and which are subject to the same time has the following conditions: on one positions is one of the numbers 1,3,4, on the place of hundreds 4 or 2.
- The confectionery
The confectionery sold 5 kinds of ice cream. In how many ways can I buy 3 kinds if order of ice creams does not matter?
- Distribution function
X 2 3 4 P 0.35 0.35 0.3 The data in this table do I calculate the distribution function F(x) and then probability p(2.5
- Ice cream
Annie likes much ice cream. In the shop are six kinds of ice cream. In how many ways she can buy ice cream to three scoop if each have a different flavor mound and the order of scoops doesn't matter?
- Phone numbers
How many 9-digit telephone numbers can be compiled from the digits 0,1,2,..,8,9 that no digit is repeated?
- Morse alphabet
Calculate how many words of Morse code to create compiling commas and dots in the words of one to five characters.
From statistics of sales goods, item A buy 54% of people and item B buys 58% of people. What is the probability that from 3 people buy 2 item A and 1 item B?
We will throw two dice. What is the probability that the ratio between numbers on first and second dice will be 1:2?
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?
The probability that the bulb can operate 4000 hours is 0.13. What is the probability that exactly one of eight bulbs can operate 4000 hours?
In the pool is numbers from 1 to 135. What is the probability that a randomly selected number is not a prime number?
In the box are 18 bulbs with power 60 W, 8 bulbs with power 40 W and 19 with 50 W. Calculate probability that a randomly selected bulb is:
- Football league
In the football league is 16 teams. How many different sequence of results may occur at the end of the competition?
If the number of elements is decreased by two the number of permutations is decreased 30 times. How many elements are?