80% choose course M and course C....., how many people choose neither M nor C?
1. 50% choose M
2. 30% choose C but not M
How do we answer this question by drawing a draft? or is there any quicker way to do it?
1. 50% choose M
2. 30% choose C but not M
How do we answer this question by drawing a draft? or is there any quicker way to do it?
















