Skyler goes to a school that has 100 students in it. She asks 40 random students if they like the new 8.30 am start to the day and 30 of them say no they don't like it. This shows that: 30/40 = 3/4 of the students don't like it.
Since the school has 100 students, the number of students that doesn't like the 8.30 a.m start will be:
