Combinatorics - problems
- Election 4
In a certain election there are 3 candidates for president 5 for secretory and 2 for tresurer. Find how many ways the election may (turn out/held).
- Perfect cubes
Suppose a number is chosen at random from the set (0,1,2,3,. .. ,202). What is the probability that the number is a perfect cube?
- A student
A student is to answer 8 out of 10 questions on the exam. a) find the number n of ways the student can choose 8 out of 10 questions b) find n if the student must answer the first three questions c) How many if he must answer at least 4 of the first 5 que
- Families 2
There are 729 families having 6 children each. The probability of a girl is 1/3 and the probability of a boy is 2/3. Find the the number of families having 2 girls and 4 boys.
In rectangle with sides 3 and 10 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?
- No. of divisors
How many different divisors has number ??
- 7 heroes
9 heroes galloping on 9 horses behind. How many ways can sort them behind?
From complete sets of playing cards (32 cards) we pulled out one card. What is the probability of pulling the ace?
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?
In how many ways can 6 shuttle vans line up at the airport?
How many ways can 7 people sit on 3 numbered chairs (eg seat reservation on the train)?
Pediatrician this month of 21 working days takes 3 days holidays. What is the probability that on Monday will be at work?
How many ways can 5 guests sit down on 6 seats standing in a row?
- 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
What is the probability that a random word composed of chars T, H, A, M will be MATH?
- 2nd class variations
From how many elements you can create 6972 variations of the second class?
How many ways are there to arrange 6 books on a shelf?
In the market have 4 kinds of chocolates. How many ways can we buy 19 chocolates?
- Phone numbers
How many 9-digit telephone numbers can be compiled from the digits 0,1,2,..,8,9 that no digit is repeated?
- Two doctors
Doctor A will determine the correct diagnosis with a probability 86% and doctor B with a probability 87%. Calculate probability of correct diagnosis if patient is diagnosed by both doctors.
Would you like to compute count of combinations?