Sex-ratio is calculated as : (1) No. of children per 1,000 people in a Country. (2) No. of males per 1,000 females in a Country. (3) No. of females per 1,000 males in a Country. (4) No. of people per 1,000 children in a Country.
(3) No. of females per 1,000 males in a Country. Explanation: Sex ratio is used to describe the number of females per 1000 of males in a region or country. Like most sexual species, the sex ratio in humans is approximately 1:1. As per the 2011 Census, Sex Ratio in India currently stands at 943 females available for every 1000 males.