Question 426852

probability of having blue eye = 20% = 20/100 = 1/5

probability of not having blue eyes = 1 - 1/5 =  4/5


probability of at least 4 have blue eyes =

probability of exactly 4 have blue eyes + probability of exactly 5 have blue 

eyes


= 5C4*(1/5)^4*(4/5)^1  + 5C5*(1/5)^5*(4/5)^0


=  5C4*(1/5)^4*(4/5)^1  + 5C5*(1/5)^5