probabilities for sitting duck, page-5

OK, Im nearly there.

I have t=2/52=.0385, and sqrt t =.1961
v =.4683
so VT=.0918
Why do you have it different?

I now have N(ln(12/11.48)*.0918)
=.5177 of being above and .4823 of being below.

So you have 31% and I have 51% because of a slight diff in VT. Who is correct? Theres still a big diff in the result, and Im a stickler for perfection.

Many thanks SD for your help.