IQ quiz!

 8

8. This satellite's crazy. Anyway.
8 hours in: 100%
10 hours in: 75%
18 hours in: 175%
20 hours in: 150%
28 hours in: 250%
30 hours in: 225%
38 hours in: 325%
40 hours in: 300%
The question is, when does it come above 0 for the third time.
Assuming they don't count hour zero (given the answers, this is ok), there is:
hour 8
hour 12
hour 24

a good method to do it, but keep in mind that from 30 hours -> 40 hours it passes over twice... once at 36 (for 300% or 3 orbits) and again at 40 (still for 300% / 3 orbits)
and claiming something is poorly written because you couldn't get a 10/10 is just plain silly. the questions are chock full of key words chosen very carefully and not to be ignored. in this case you and kalovale mistook "orbits" for "passes". in my case i missed "second largest area" and a lack of any restrictions on x. it sucks to misread, but it's human.