The letters of the word ‘ZENITH’ are written in all possible orders. How many words are possible if all these words are written out as in a dictionary? What is the rank of the word ‘ZENITH’?
E-----=5!
H------=5!
I------=5!
N-----=5!
T-----=5!
ZEH---=3!
ZEI---=3!
ZENH--=2!
ZENTHI=1!
ZENITH=1!.....SO RANK IS 616