Hi I have one observation regarding q12.19 and the exam type question given at the back (first question part c) For instance in Q12.19 to find MLE L(theta)=prod 6Cxi theta ^xi (1-theta)^(6-xi) This can also be written as which I think is simpler to write but tedious to solve (as mentioned in the exam type question part c) P(N=0)^38.P(N=1)^70.... Both of the expressions are giving the same MLE My question is in the solution to Q12.19 what is the the sigma (xi) represent. They have taken it as 301 which is 0*38+1*70+... I'm not able to understand what sigma xi represents. does it represent the expected no of bottles containing impurities?. Will not P(N=0)^38.P(N=1)^70.... method fits in everytime?