Permutations an...

12 boys and 2 girls are to be seated in a row such that there are atleast 3 boys between the 2 girls.The no.of ways this can be done is m.12! where m =________

The first 12 letters of the english alphabet are to be written at random so that there are exactly 4 letters between A and B. the number of ways this can be done is _______?

How many different words canbe formed by the letters of the word MISSISSIPPI in which no two S are adjacent ?

From 6 different novels and 3 different dictionaries 4 novels and, 1 dictionary are to be selected and arranged in a row on the shelf so that the dictionary is always in the middle.Then the no, of such arrangements is _______

At an election 3 wards of a town are convassed by 4,5 and 8 men respectively. If there are 20 volunteers then the no. of ways they can be alloted to different wards is ?

A round table conference is to be held among 20 delegates of 20 countries.The no, of ways they can be seated if two particular delegates are never sit together is.

Ten different letters of an alphabet are given Words with 5 letters are formed from the given letters. The no, of words which have atleast one letter repeated is _______

8 chairs are numbered 1 to 8 Two women and 3 men wish to occupy one chair each first the women choose the chairs marked, 1 to 4 then the men select from among the remaining chairs. The no, of seating arrangments is

There are 4 balls of different colours and 4 boxes of colours same as those of the balls. The no, of ways in which the balls, one in each box could be placed such that a ball does not go to a box of its own colour is _______