I had the same exam in Maths in uni at the start of the year , there were a huge amount of easy questions based on high-school / first / second year uni maths , so people thought that would be easy and were delighted ! As there were a lot of exercises ( like studying functions and complex numbers ) , they were focused on doing them and they didn't have time to see the last bit lol ! Needless to say 90% failed the exam lol