math
posted by ani .
If 96% of Chinese couples have one child (which is female 50% of the time), and the remaining 4% of Chinese couples engage in sexselective abortion until they have a male child, what is the ratio of females per 100 males among the children (to the nearest whole number)?

The 96% who do not select will contribute 48% of the females and 48% of the males. The 4% who do select will contribute all males, so 52% will be males and 48% females.
That means 48 females per 52 males or 92.3 females per 100 males.
(You get that by solving 48/52 = x/100)
Per nearest whole number, that is 92 females. 
thanks a lot