Lizzy: 20 kids in preschool are ready for a nap. 1/2 of the kids fall asleep within the first 5 minutes. Then half of the kids remaining fall asleep within another 5 minutes. How many kids are still awake?.
Me: Hmmm, let me think. I think this is the detailed solution:
In a class with 20 kids, 1 / 2 of the students have already fallen asleep so 20 / 2 = 10 kids are already asleep. We start with 20 kids awake and 10 are already asleep so 20 - 10 = 10 kids are still awake. 1 / 2 of these 10 kids fall asleep next meaning there are 10 / 2 = 5 students still awake. Final answer: 5.