Subject: mathqa
Question: at the faculty of aerospace engineering , 312 students study random - processing methods , 232 students study scramjet rocket engines and 112 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 ?
Option: 
A: 436
B: 424 .
C: 428 .
D: 432 .
Answer: D