how many 4 letter words can be formed by the word AAKASH?

we cant define it because u didnt gave us clarity wether they should be meaningful or not.

if not required.5!=120 words are possible

Taking one ''A'' at a time (AKSH) 4!=24 words can be formed.

Taking 2 ''A''s at a time (AAKS, AAKH, AASH) 4!/2!+4!/2!+4!/2!=36 words ca be formed.

Taking 3 ''A''s at atime (AAAS,AAAK,AAAH)4!/3!+4!/3!+4!/3!=12 words can be formed.

adding all this 36+12+24=72 words can be formed...