# Combinatorics - examples

- Inverted nine

In the hotel,, Inverted nine" each hotel room number is divisible by 6. How many rooms we can count with three-digit number registered by digits 1,8,7,4,9? - PIN code

PIN on Michael credit card is a four-digit number. Michael told this to his friend: • It is a prime number - that is, a number greater than 1, which is only divisible by number one and by itself. • The first digit is larger than the second. • The second. - Mumbai

A job placement agency in Mumbai had to send ten students to five companies two to each. Two of the companies are in Mumbai and others are outside. Two of the students prefer to work in Mumbai while three prefer to work outside. In how many ways assignment - No. of divisors

How many different divisors has number ?? - Rectangle

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

9 heroes galloping on 9 horses behind. How many ways can sort them behind? - Ace

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

How many different flags can be made from colors purple, yellow, red, white, blue, green, orange so that each flag consisted of three different colors? - Vans

In how many ways can 7 shuttle vans line up at the airport? - Seating

How many ways can 10 people sit on 0 numbered chairs (eg seat reservation on the train)? - Pediatrician

Pediatrician this month of 21 working days takes 3 days holidays. What is the probability that on Monday will be at work? - Guests

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 - 2nd class variations

From how many elements you can create 6972 variations of the second class? - Word

What is the probability that a random word composed of chars T, H, A, M will be MATH? - Shelf

How many ways are there to arrange 6 books on a shelf? - Chocolates

In the market have 4 kinds of chocolates. How many ways can we buy 23 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. - Rectangles

How many rectangles with area 3002 cm^{2}whose sides is natural numbers are?

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