Logic Question.

Okay guys so. I took a Bio-Statistics class. But my teacher is Russian or one of those countries, so the way he teaches is eccentric. He teaches crazy stuff that goes along with the textbook, but he does it in a way that reading the textbook won't help you if you don't pay attention and understand HIM, then you won't do well on his tests.

He gave a test last Thursday. And it's Spring Break this week, so I won't see him again till next next Monday (the 14th). There was this one question on the test that had to do kind of with logic, he never taught us anything like it, and it wasn't mentioned in the book. I'm dying to know the answer to this question. I did it on my test, but I'm not sure if the answer is right since I was pressured with time and submitted the first thing I got. Here it goes:

There was a study of 100 sophomores in a school to check how many received financial aid. It was found that 49 people used Government Grants, 55 people used Private Scholarships, and 43 people used Academic Credits; 18 people used both Government Grants and Private Scholarships, 28 people used both Government Grants and Academic Credits, and 8 people used all three. Find out how many students use at least one type of scholarship.

So essentially:
49 A
55 B
43 C
18 A + B
28 A + C
8 A + B + C

I'll say the answer I put after one of you smart people figure out how to do it. Thanks in advance.