What is the probability of by "Pullets" being roosters?

[Rolison]

I went to Family Home and Tractor (Like Tractor Supply) and got 4 chicks. On there boorder it said Pullets but what is the probability of some of them being roosters? Also what is the probability of them not making it to adulthood in other words dieing.

 

[sumi]

Sometimes a roo does slip through with the sexing, but less than 1% I'd say.
Chicks do die for all sorts of reasons. But of you keep them warm, fed, watered and safe and check for pasty butt and lice etc they should be o.k. I've had many many chicks and very few died for no apparent reason.

 

[Rolison]

Thank you. I feel much better now.