document.write( "Question 913261: A recent survey found that 50% of mobile phone users, between the ages of 18 to 34, had a smartphone. Suppose a random sample of 20 mobile phone users were selected. What is the probability that less than 5 of them have a smartphone? [Ensure that you (a) clearly denote the probability distribution and its parameter(s) and its parameter(s) and (b) state the formula].\r
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Algebra.Com's Answer #554387 by ewatrrr(24785)\"\" \"About 
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Binomial Distribution: p(have) = .50, n = 20
\n" ); document.write( "P(x < 5) = binomcdf(20, .50, 4) Using TI
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\n" ); document.write( "Computed Individually and sum determined.
\n" ); document.write( "Using \"P+%28x%29=+highlight_green%28nCx%29%28p%5Ex%29%28q%29%5E%28n-x%29+\"
\n" ); document.write( "p and q are the probabilities of success and failure respectively.
\n" ); document.write( "In this case p = .50 and q = .50, n = 20
\n" ); document.write( "\"nCx+=+%28n%21%29%2Fx%21%28n+-+x%29%21%29\"
\n" ); document.write( "P(x < 5) = P(0) + P(1) + P(2) + P(3) + P(4)
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