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Question : In 2013, only 26% of Americans had


In 2013, only 26% of Americans had confidence in U.S. banks, which is still far below the pre-recession level of 41% reported in June 2007 (www.gallup.com, June 26, 2014).
a. What is the probability that fewer than half of four Americans in 2013 have confidence in U.S. banks?
b. What would have been the corresponding probability in 2007?