How many four digit numbers can be formed using the digits {4, 5, 6, 8, 7, 9}? (repetition of digits is not allowed)

PERMUTATION AND COMBINATION :

There are 23 stations between Delhi and Chennai. How many first class tickets have to be printed, so that a passenger can travel from any station to any other station?

PERMUTATION AND COMBINATION :

A number lock consists of three rings each marked with seven different numbers. The number of distinct unsuccessful attempts to open the lock is at the most________.

PERMUTATION AND COMBINATION :

How many four digit numbers can be formed using the digits {4, 5, 6, 8, 7, 9}? (repetition of digits is not allowed)

PERMUTATION AND COMBINATION :

How many four digit even numbers can be formed using the digits {6, 1, 3, 5, 7, 9} (repetition of digits is not allowed)?

PERMUTATION AND COMBINATION :

In how many ways can three consonants and two vowels be selected from the letters of the word "FASHION"?

PERMUTATION AND COMBINATION :

In a class there are 30 boys and 35 girls. In how many ways can a boy and a girl be selected?

PERMUTATION AND COMBINATION :

In how many ways can a committee consisting of five men and six women be formed from a group of eight men and nine women?

PERMUTATION AND COMBINATION :

A  paper consists of six questions, each question having four internal choices. In how many ways can a candidate attempt one or more questions?

PERMUTATION AND COMBINATION :

Eight points are marked on a straight line and Nine points are marked on another line which is parallel to the first line. How many straight lines, including the first
two, can be formed with those points?

PERMUTATION AND COMBINATION :

In how many ways can six boys and five girls sit in a row such that all boys sit together?