Find the number of ways of selecting 5 books from 9 different mathematics books such that a particular book is not included.

Find the number of ways of arranging 5 different mathematics books, 4 different Physics books and 3 different chemistry books such that the books of the same subject are together.

The number of ways of selecting 8 books from a library which has 9 books each of Mathematics, Physics, Chemistry and English is:

The number of ways in which n books can be arranged on a shelf so that two particular books are not together is

The number of ways of selecting 8 books from a library which has 9books each of Mathematics,Physics,Chemistry and English is:

From 12 books, the difference between number of ways a selection of 5 books when one specified book is always excluded and one specified book is always included is

From 12 books, the difference between number of ways a selection of 5 books when one specified book is always excluded and one specified book is always included is