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Homework Help: Problem from discrete math class

  1. Sep 19, 2013 #1
    How would I go about solving this?
    We are starting to learn about venn diagrams so would creating a venn diagram be helpful?

    This is what I tried so far, I created a set C consisting of all people who have taken calculus and a set D consisting of all people who have taken discrete math.

    |C| = 331
    |D| = 217
    |C^D| = 199.

    How can I determine the value of |C or D|?

    |C^D| = number of people who have taken D and C

    |C or D| = number of people who have taken D or C.

    Attached Files:

  2. jcsd
  3. Sep 19, 2013 #2


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    Science Advisor
    Homework Helper

    Creating a Venn diagram would be very helpful. There's an inclusion-exclusion identity connecting all of those numbers. |C or D|=|C|+|D|-|C and D|. The diagram should make it obvious.
  4. Sep 19, 2013 #3


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    Staff: Mentor

    Miike, please do not delete the homework template, you must type everything out, attaching files in lieu of typing out the information is not allowed. It's also very inconsiderate to expect members to read something as hard to read as what you posted. I have typed it out above.

    Helpers, please remember to report any thread where the template is not used and/or is not properly filled out.

    Last edited: Sep 19, 2013
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