In Fall 2011, the Wall Street Journal reported that 44% of smartphone purchases made by people with incomes between $35,000 to $50,000 were Android phones.16
(a) If the story is based on a sample of 200 purchases, then should we conclude that Android phones were getting less than half of the market at that time?
(b) How large a sample is needed for the 95% confidence interval for the population proportion to exclude 50%?
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