Question 658812
   <pre><font face = "Tohoma" size = 3 color = "indigo"><b> 
Hi,
Example of BIONOMIAL PROBABILITY DISTRIBUTION
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(scout) = 2/5 & q = 3/5   and n = 8
nCx = {{{n!/(x!(n-x)!)}}}
8 boys be selected, so as to include 
P(x = 3) = 8C3(.4)^3(.6)^5
P(x &#8805; 3) = 1- P(x&#8804; 2)= 1 - P(x=0) + P(x=1)+ P(x=2)
P(x &#8804; 3) = P(x=0) + P(x=1)+ P(x=2)+ P(x=3)