The first name of a person consists of 8 letters in which one letter occurs more than once while the other letters are different . If the number of permutations of the letters of his name taken all at a time be 6720 , find the number of times the like letter occurs.

The first name of a person consists of 9 letters in which one letters occurs more than once and the other letters are different . If the numbers of permutations of the letters of his name taken all at a time be 15120 , find the number of times the like letters occurs .

Find the number of permutations of the letters x,x,x,y,y,y,z,w taken 5 at a time.

Find the number of permutations in the letters of the word PROPORTION taken 4 at a time .

Find the number of permutations of the letters of the word ALLAHABAD.

Find the number of permutations in the letters of the word ACCOUNTANCY taken 4 at a time .

Find the number of combinations in the letters of the word STATISTICS taken 4 at a time .

The number of arrangements of the letters of the word BHARAT taking 3 at a time is

In how many of the permutations of the letters in the word SYNDICATE taken 4 at a time , there shall be no vowel

The number of permutations of n different things taken r at a time in which 4 particular things never occur is -

Find the number of permutations of letters a ,b ,c ,d ,e ,f,g taken all together if neither beg nor cad pattern appear.