
Concept explainers
In Exercises 43-48, construct a Venn diagram and determine the cardinality for each region. Use the completed Venn diagram to answer the questions.
An anonymous survey of college students was taken to determine behaviors regarding alcohol, cigarettes, and illegal drugs. The results were as follows: 894 drank alcohol regularly, 665 smoked cigarettes, 192 used illegal drugs, 424 drank alcohol regularly and smoked cigarettes, 114 drank alcohol regularly and used illegal drugs, 119 smoked cigarettes and used illegal drugs, 97 engaged in all three behaviors, and 309 engaged in none of these behaviors.
Source: Jamie Langille, University Of Nevada Las Vegas
a. How many students were surveyed?
Of those surveyed,
b. How many drank alcohol regularly or smoked cigarettes?
c. How many used illegal drugs only?
d. How many drank alcohol regularly and smoked cigarettes, but did not use illegal drugs?
e. How many drank alcohol regularly or used illegal drugs, but did not smoke cigarettes?
f. How many engaged in exactly two of these behaviors?
g. How many engaged in at least one of these behaviors?

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Chapter 2 Solutions
Thinking Mathematically, Books a la Carte Plus MyLab Math -- Access Card Package (7th Edition)
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