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18. (3 marks). An advertising campaign aimed at promoting a new brand of laptop to university
students was being designed when the Marketers decided they needed to investigate how different
wording options may influence consumer perceptions.
The Marketers recruited 100 university students into their study by posting flyers around the
campus of one university, and selecting the first 100 students that responded. They then ran-
domly assigned 50 students to read Campaign A, while the other 50 students to read Campaign
B. All students were then asked whether or not they would likely buy this brand of laptop.
(a) Was this an observational study or a designed experiment?
Justify your response
in one
sentence
.
(b) Identify
two
sources of bias that may influence the results of this study.
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19. (4 marks). A national survey determined that approximately 60% of Canadians conduct their
banking online. Of those who conduct their banking online, 75% of them are under the age of
50. Of the Canadians that do not do their banking online, 35% of them are under the age of 50.
Use this information to answer the following questions. You must show your work for full marks.
(a) What is the probability a randomly selected Canadian is under the age of 50
and
conducts
their banking online?
(b) What is the probability a randomly selected Canadian is under the age of 50?
(c) Are the events
“conducts banking online”
and
“under the age of 50”
independent events?
Justify your response.
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