If you have 205 students, and only 4 open positions, there would be multiple possibilities. For this question I would multiply 4 by 205, in which would contain every single possibility. 4 positions, 205 students, 4 times 205 would be 820 possibilities. Hope this helps.
The inequality is: x < 90 ( or x is less than 90 ). Answers A and D are represented by: x > 90. Answer B is represented by: x = 90. Therefore this situation is: C ) A kiddie pool holds under 90 L of water.