# Discrete Math: Set Theory

Can anyone help me check if my solution is correct?

Link here, sorry it kinda look too messy when i tried to paste

d) A class has 175 students. The following table shows the number of students studying one or more of the following subjects.

Subject                                         No. of students
Mathematics                                           100
Physics                                               70
Chemistry                                             46
Mathematics and Physics                               30
Mathematics and Chemistry                             28
Physics and Chemistry                                 23
Mathematics, Physics and Chemistry                    18


(i) How many students are enrolled in Mathematics alone, Physics alone and Chemistry alone?
(ii) Are there students who have not been offered any one of these subjects? Provide your explanation using a Venn diagram.

SOLUTION:

Solution temporarily hidden to avoid plagiarism by other students (edited by question owner)


Therefore, students who took Mathematics alone is 62, students who took Physics alone is 37 and students who took Chemistry alone is 31.

Thanks to brian for pointing the arithmetic error :)

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I think you needed to provide more context and actually wrote out where you are having issues. Some people find "check my homework" to be rude behavior and items are better posted as questions asking for guidance and help. Regards – Amzoti Mar 9 '13 at 17:39
@Natsume I've tried to add information from your paste to the post; I hope the formatting is acceptable. You can get some basic help by clicking on questionmark icon when editing and also here. – Martin Sleziak Mar 9 '13 at 18:23
@MartinSleziak thanks! – Natsume Mar 10 '13 at 3:23
@Amzoti it is a kind of my coursework too, but at least i tried to make a solution and asked here if my solution is correct. I f it's wrong so i can learn where is the error like brian pointed out – Natsume Mar 10 '13 at 3:30
@Natsume: I am not the police, I just saw that your post had been down-voted several times and was trying to point out what that could have happened. It is okay to post such things, but understand that it needs the appropriate context - that is the only point I was trying to make. Regards – Amzoti Mar 10 '13 at 3:32

Your approach is correct, but you made an arithmetic mistake near the beginning that threw everything off: $30-18=12$, not $28$, so $e=12$. I get $60$, $35$, and $13$, respectively, for the numbers of students taking only mathematics, only physics, and only chemistry.