At my office, $16$ people own cats, $9$ people own dogs, and $3$ people own both cats and dogs. How many people own a cat or a dog?
(Remember that in mathematics, the word "or" is used in the inclusive sense. So if you own both a cat and a dog, then you are included in the category of people "who own a cat or a dog".)
+37146 Here is a Venn diagram
WHen you ask 'or' for a two subject Venn , you include everyone (sorry....I got the 'dog' and 'cat' labels backwards....result is the same )
so 13 + 3 + 6 = ____________
