09 Binomial Distribution Student Filled In.notebook
October 29, 2013
Ex. 7: The CBS television show 60 Minutes has been successful for many years. That show recently had a share of 20, meaning that among the TV sets in use, 20% were tuned to 60 Minutes (based on data from Nielsen Media Research). For a survey of 10 households, find the following:
a) Find the probability that none of the households are tuned to 60 Minutes.
b) Find the probability that at least one household is tuned to 60 Minutes.
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09 Binomial Distribution Student Filled In.notebook
October 29, 2013
Ex. 8: Walmart knows that 5% of a certain model of television they sell are defective. They get in a shipment of 12 TVs from the manufacturer. What is the probability that at least one TV is defective?
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09 Binomial Distribution Student Filled In.notebook
October 29, 2013
Mean and Standard Deviation for Binomial Distributions
Having a binomial distribution makes finding µ and σ easy!
Mean: _____________________________________________ Standard deviation: _________________________________
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09 Binomial Distribution Student Filled In.notebook
October 29, 2013
Ex. 9: Your friend said he had a bag of 20 M&Ms that was half blue. You know that the probability of getting a blue M&M is 15%. Does his claim seem likely?
a) Use the mean and standard deviation to determine if his bag is unusual.
b) What is the probability of having 10 blue M&Ms?
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09 Binomial Distribution Student Filled In.notebook
October 29, 2013
Ex. 10: In a test of the MicroSort method of gender selection, 325 babies are born to couples trying to have baby girls, and 295 of those babies are girls (based on data from the Genetics & IVF Institute).
a) If the gender­selection method has no effect and boys and girls are equally likely, find
the mean and standard deviation for the numbers of girls born in groups of 325.
b) Is the result of 295 girls unusual? Does it suggest that the gender­selection method
appears to be effective?
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09 Binomial Distribution Student Filled In.notebook
October 29, 2013
Ex. 11: When Mendel conducted his famous genetics experiments with peas, one sample of offspring consisted of 580 peas, and Mendel theorized that 25% of them would be yellow peas.
a) If Mendel’s theory is correct, find the mean and standard deviation for the number of
yellow peas in a group of 580 offspring peas.
b) The actual results consisted of 152 yellow peas. Is that result unusual? What does this
result suggest about Mendel’s theory?
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09 Binomial Distribution Student Filled In.notebook
October 29, 2013
Ex. 12: In a study of 420,095 cell phone users in Denmark, it was found that 135 developed cancer of the brain or nervous system. If we assume that such cancer is not affected by cell phones, the probability of a person having that kind of cancer is 0.000340.
a) Find the mean and standard deviation for the number of people who develop cancer of
the brain or nervous system in a group of 420,095.
b) Based on these results, is it unusual to have 135 cases of cancer? c) What do these results suggest about the publicized concern that cell phones are a health
danger because they increase the risk of cancer of the brain or nervous system?
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