For Binomial and poisson questions, do we need to show working if the question can be done on a graphical calculator.
Example:
Number of misprints per page has Poisson, mean of 2.5,
Find probability of no misprints(2 marks),
If I just write X~Po(2.5)
P(X=0)=0.0821
Will I still get full marks even though in the mark scheme, you get an M1 for doing P(X<=1)-P(X<=0)?