Question 913261
Binomial Distribution: p(have) = .50,  n = 20
P(x < 5) = binomcdf(20, .50, 4) Using TI
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Computed Individually and sum determined.
Using {{{P (x)= highlight_green(nCx)(p^x)(q)^(n-x) }}} 
p and q are the probabilities of success and failure respectively. 
In this case p = .50 and q = .50, n = 20 
{{{nCx = (n!)/x!(n - x)!)}}} 
P(x < 5) = P(0) + P(1) + P(2) + P(3) + P(4)