Hi,

I've been struggling with this for the last couple of days. I would appreciate any illumination.

Let and be independent random variables where and with

Show that the conditional pdf of given is binomial with parameters and .

For notation I say N is the random variable taking a value N =n.

So then as I see it,

so

Which I reckon simplifies to

Which seems plausible, but I can't massage it into a binomial with parameters and

Thanks in advance for any light anyone can throw on this. MD