n articles are arranged in such a way that 2 particular articles never come together. Thenumber of such arrangements is

Letters of the word DIRECTOR are arranged in such a way that all the vowels come together. Find out the total number of ways for making such arrangement.

If n things are arranged at random in a row then the probability that m particular things are never together is -

In how many ways can 8 students be arranged at a round table so that 2 particular students may be together, if (i) students are arranged with respect to table?

In how many ways can the word STRANGE be arranged so that the vowels never come together

In how many ways can 12 papers be arranged if the best and the worst paper never come together?

You are given 8 balls of different colour (black,white ......). The number of ways in which these balls can be arranged in a row so that the two balls of particular colour (say red and white) may never come together is-

You are given 8 balls of different colour (black,white ......). The number of ways in which these balls can be arranged in a row so that the two balls of particular colour (say red and white) may never come together is-