To solve you start by dividing 25,000 in half. This gives you 12,500. Then you subtract 240 from it to find the number of females (12,260). Finally you subtract 12, 260 from 25,000 to find the number of males.
A kitten’s mass at birth was 0.09 kilogram. The kitten gained approximately 0.084 kilogram each week. After how many weeks is the kitten’s mass 1.098 kilograms?