How many words of four letter can be constructed by using the letters of the words CHEMISTRY(may not be meaningful)?

How many words with or without meaning can be formed using all the letters of the words EQUATION using each letter exactly once?

How many triangles can be obtained by joining the vertices of a quadrilateral?

Find how many words can be formed of the letters of the words:COMBINE so that the vowels may never seperated.

Find how many words can be formed of the letters of the words: DAUGHTER so that the vowels may never seperated.

Find how many words can be formed of the letters of the words: FAILURE so that the vowels may never seperated.

How many arrangements are possible with the letters of the word. ENGINEERING?

In how many ways can one post 3 letters in 5 post boxes?

How many different committee of four members can be formed out of eight players?

How many types of matrices can be formed from 8 elements ?

How many triangles can be obtained when the vertices of a hexagon are joined?