I have a task:
In a class of 65, there are twice as many maths students as biology students. If 12 biology students do not take maths and 15 students take neither of these subjects, how many students take maths but not biology?
E. This is impossible
I found out that the result is 31 (Answer D) but only by using the answer as help. Is there another mathematical way? I tried out a lot but I couldn't find out.