SOLUTION: A survey of a group's web habits for the past month obtained the following information.
30% visited Facebook.
38% visited LinkedIn.
36% visited Google.
16% visited Facebook a
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-> SOLUTION: A survey of a group's web habits for the past month obtained the following information.
30% visited Facebook.
38% visited LinkedIn.
36% visited Google.
16% visited Facebook a
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Question 1205866: A survey of a group's web habits for the past month obtained the following information.
30% visited Facebook.
38% visited LinkedIn.
36% visited Google.
16% visited Facebook and LinkedIn.
16% visited Facebook and Google.
18% visited LinkedIn and Google.
9% visited all three sites.
Find the percentage that visited none of these three sites last month.
Hint: Draw a Venn diagram for three sets. Then label appropriate parts from the given information. Answer by ikleyn(52776) (Show Source):
Find the percentage of those who visited at least on of the three sites.
Use the Inclusion-Exclusion principle/formula
30% + 38% + 36% - 15% - 16% - 18% + 9% = 64%.
The percentage of those who visited none of these three sites last month
is the complement of 64% to 100%, i.e. 100% - 64% = 36%.
ANSWER. 36%.
Solved.
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On inclusion-exclusion principle, see this Wikipedia article
