Sex ratio is
Sex ratio is defined as the number of females per 1000 males. It is one of the basic demographic characteristic of a population. Reference : Park&;s textbook of preventive and social medicine, 23rd edition, pg no:482
1 male per 1000 females
1000 females for 1000 males
Number of female for 1000 males
1000 females per 100000 males
Demography and family planning