Question 870619
p (red) = .20,  n = 15
a) P(x ≥ 3) = 1 - binomcdf(15, .20, 2)= .602 
0r
{{{P (x)= highlight_green(nCx)(p^x)(q)^(n-x) }}} 
1 - P(0) + P(x=1) + P(x=2) = 1 - (.035 + .132 + .231) = 1 - .398 = .602
b) p (red) = .20, n = 6
  P(x ≤ 5) = 1 - p(x = 6) = 1 - (.2)^6 = 1 - .0001 = .9999