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Chapter 11: Q2CRE (page 533)

Chocolate and Happiness In a survey sponsored by the Lindt chocolate company, 1708 women were surveyed and 85% of them said that chocolate made them happier.

a. Is there anything potentially wrong with this survey?

b. Of the 1708 women surveyed, what is the number of them who said that chocolate made them happier?

Short Answer

Expert verified

a. There could be a potential bias created by the chocolate company as the survey was sponsored by the company and in order to show favorable results, the outcomes might be false.

b. The number of women who said that chocolate made them happier is equal to 1452.

Step by step solution

01

Given information

It is given that a chocolate company sponsored a survey.

Out of 1708 women who were surveyed, 85% of them said that chocolate made them happier.

02

Limitation of the survey

a.

Because the poll was sponsored by the chocolate firm, there could be a potential bias produced by the company, and the results could be deceptive in order to portray favourable results.

03

Conversion of proportion to the number

b.

The proportion of women who said that chocolate made them happier is equal to 85%.

The sample size is equal to 1708.

Thus, the corresponding number of women is computed below:

\(\begin{aligned}{c}85\% \;{\rm{of}}\;1708 = \frac{{85}}{{100}} \times 1708\\ \approx 1452\end{aligned}\)

Thus, the number of women who said that chocolate made them happier is equal to 1452.

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