Two Basic Rules of Probability · Exercise 12
A survey was conducted in a large city to measure the popularity of that city’s mayor. The survey was repeated every year for three years. The survey polled 1,046 people to measure the mayor’s popularity. Everyone polled expressed either approval or disapproval. These are the results the poll produced:
• In Year 1, 60% of the population approved of the mayor’s actions in office.
• In Year 2, 57% of the population approved of his actions.
• In Year 3, the percentage of popular approval was measured at 42%.
(a) What is the sample size for this study?
(b) What proportion in the poll disapproved of the mayor, according to the results from Year 3?
(c) How many people polled responded that they approved the mayor based on results from Year 3?
(d) What is the probability that a person supported the mayor, based on the data collected in Year 2?
(e) What is the probability that a person supported the mayor, based on the data collected in Year 1?
OpenStax, Introductory Statistics 2e · §3.3 Two Basic Rules of Probability · Exercise 12
No hints for this one.
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