- #1
kerrwilk
- 14
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Homework Statement
There are 54 books in a book store: 28 are fiction, 21 are humour and 17 are children’s books. If 12 of the books are humourous fiction, 8 are children’s fiction, 3 are humourous fiction for children and 10 are serious non-fiction for adults, how many books are non-fiction humour for children.
Homework Equations
n(total) = n(C) + n(F) + n(H) – n(C + F) – n(C + H) – n(F + H) + n(F + C + H)
The Attempt at a Solution
Let x= the number of non-fiction humour for children.
n(total) = n(C) + n(F) + n(H) – n(C + F) – n(C + H) – n(F + H) + n(F + C + H)
44 = (9-x+5+3+x) + (11+9+3+5) + (9+3+x+9-x) – (5+3) – (3+x) – (3+9) + 3
44 = 46 –x
-2 = -x
x=2
I am a bit confused by the wording. Does "28 are fiction" mean that there are 28 books that are only fiction (and nothing else) or does it mean there are 28 fictional books including the humourous fiction and children’s fiction? I took it to mean the latter. Did I do this correctly? Thanks for your help.
My Diagram is attached.