Question 442720
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Hi
about 50% of male Internet users in this age group visit an auction site such
 as eBay at leat once a month. 
random sample of 12 male Internet users aged 18-34.
Find the probability that at least 8 of the 12 have visited an auction site in the past month!
 P(at least 8 of 12) = P(8 &#8804; x &#8804; 12) = .1938

Note: The probability of x successes in n trials is: 
P = nCx* {{{p^x*q^(n-x)}}} where p and q are the probabilities of success and failure respectively. 
In this case p & q are = .5
nCx = {{{n!/(x!(n-x)!)}}}