At the faculty of Aerospace Engineering, 312 students study Random-processing methods, 232 students study Scramjet rocket engines and 114 students study them both. If every student in the faculty has to study one of the two subjects, how many students are there in the faculty of Aerospace Engineering?  Choose the most appropriate option
A) 438 B) 436 C) 430 D) 442 E) 444

Rationale: 312 + 232 - 114 ( since 112 is counted twice ) = 430 c is the answer
Answer: C