A group of 300 athletes spent Saturday night at Ultimate Fitness Camp. The next morning, for 4 hours straight, they left the camp at a rate of 28 athletes per hour. Over the next 7 hours, a new group of athletes trickled into the camp at a rate of 15 athletes per hour. Immediately thereafter, the camp gate was shut and everyone went to bed. What is the difference in the total number of athletes in the camp over the two nights? Give me reasons, before answering the question
The number that left the camp on Saturday morning was 4 * 28 = 112 athletes. This means that in the camp there remained 300 - 112 = 188 athletes. The new group trickling in on Sunday morning comprised 7 * 15 = 105 athletes. The number that slept at the camp on Sunday night is therefore 188 + 105 = 293 athletes. Since there were 300 athletes on Saturday night, the difference is 300 - 293 = 7 athletes. So the final answer is 7.