# Combinatorics - problems

Would you like to compute count of combinations?- No. of divisors

How many different divisors has number ?? - Ace

From complete sets of playing cards (32 cards) we pulled out one card. What is the probability of pulling the ace? - Toys

3 children pulled 9 different toys from a box. Many ways can be divided toys so that each children had at least one toy? - 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? - Examination

The class is 22 students. How many ways can choose four to examination? - Probabilities

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? - 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? - 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 - First class

The shipment contains 40 items. 36 are first grade, 4 are defective. How many ways can select 5 items, so that it is no more than one defective? - Two aces

From a 32 card box we randomly pick 1 card and then 2 more cards. What is the probability that last two drawn cards are aces? - 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. - Sales

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? - Dices

We will throw two dice. What is the probability that the ratio between numbers on first and second dice will be 1:2? - 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? - Bulbs

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? - Raffle

In the pool is numbers from 1 to 135. What is the probability that a randomly selected number is not a prime number? - Bulbs

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:

Do you have interesting mathematical problem that you can't solve it? Enter it and we can try to solve it.