Permutations an...

A lady arranges a dinner party for 6 guests .The number of ways in which they may be selected from among 10 friends if 2 of the friends will not attend the party together is

How many words can be formed by taking four different letters of the word MATHEMATICS?

H.C.F. of n !, (n + 1) ! and (n + 2) ! is

The number of ways in which one or more balls can be selected out of 10 white, 9 green and 7 blue balls is

A coin is tossed n times, the number of all the possible outcomes is

In how many ways can a garland be made from exactly 10 flowers?

The number of all three digit even numbers such that if 5 is one of the digits then next digit is 7 is

Out of 9 consonants and 5 vowels, how many words of 3 consonants and 3 vowels can be formed?

In how many ways can a mixed doubles tennis game be arranged from a group of 10 players consisting of 6 men and 4 women

If no husband and wife play in the same game, then the number of ways in which a mixed double game can be arranged from among nine married couples is