Combinatorics - problems
- Cancel fractions
Compress the expression of factorial: (n+6)!/(n+4)!-n!/(n-2)!
- Normal distribution GPA
The average GPA is 2.78 with a standard deviation of 4.5. What are students in the bottom the 20% having what GPA?
- No. of divisors
How many different divisors has number ??
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?
- 7 heroes
5 heroes galloping on 5 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 red, blue, green, white, yellow so that each flag consisted of three different colors?
In how many ways can 5 shuttle vans line up at the airport?
How many ways can 7 people sit on 2 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?
- 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
How many ways can 8 guests sit down on 10 seats standing in a row?
- 2nd class variations
From how many elements you can create 6972 variations of the second class?
What is the probability that a random word composed of chars H, T, M, A will be MATH?
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 23 chocolates?
- Phone numbers
How many 7-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 92% and doctor B with a probability 88%. Calculate probability of correct diagnosis if patient is diagnosed by both doctors.
How many rectangles with area 3002 cm2 whose sides is natural numbers are?
- Football league
In the 5th football league is 10 teams. How many ways can be filled first, second and third place?
Would you like to compute count of combinations?